We've searched the internet and found the largest collection of On30 Scale trains for sale is on eBay. Below are the listings for 'box car'.

BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 603
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 603
$64.16
Time Remaining: 1h 55m
Buy It Now for only: $64.16
A Plan For VIctory Box Car Hawthorne Village Civil War Confederate Express MIB
A Plan For VIctory Box Car Hawthorne Village Civil War Confederate Express MIB
$64.99
Time Remaining: 1d 1h 54m
Buy It Now for only: $64.99
On30 Fat Albert Boxcar Conversion to fit Bachmann 18ft flat car
On30 Fat Albert Boxcar Conversion to fit Bachmann 18ft flat car
$37.00
Time Remaining: 4d 3h 26m
Buy It Now for only: $37.00
Bachmann On30 Scale Train 18 Freight Cars Low Gondola 2 box 26531
Bachmann On30 Scale Train 18 Freight Cars Low Gondola 2 box 26531
$69.24
Time Remaining: 5d 6h 29m
Buy It Now for only: $69.24
Bachmann On30 Scale Train 18 Freight Cars Box Car 2 per box 26501
Bachmann On30 Scale Train 18 Freight Cars Box Car 2 per box 26501
$91.82
Time Remaining: 5d 6h 29m
Buy It Now for only: $91.82
Bachmann On30 Scale Train 18 Box Car W Murphy Roof Gray 2 box 26553
Bachmann On30 Scale Train 18 Box Car W Murphy Roof Gray 2 box 26553
$91.82
Time Remaining: 5d 6h 29m
Buy It Now for only: $91.82
Bachmann On30 Scale Train 18 Freight Cars High Gondola 2 box 26541
Bachmann On30 Scale Train 18 Freight Cars High Gondola 2 box 26541
$74.51
Time Remaining: 5d 6h 29m
Buy It Now for only: $74.51
Bachmann On30 Scale Train Box Car South Pacific Coast Sunset Logo 27002
Bachmann On30 Scale Train Box Car South Pacific Coast Sunset Logo 27002
$45.91
Time Remaining: 5d 6h 31m
Buy It Now for only: $45.91
Bachmann On30 Scale Train Box Car Mineral Red Data Only 27098
Bachmann On30 Scale Train Box Car Mineral Red Data Only 27098
$45.91
Time Remaining: 5d 6h 31m
Buy It Now for only: $45.91
Bachmann On30 Scale Train Box Car Oxide Red Data Only 27097
Bachmann On30 Scale Train Box Car Oxide Red Data Only 27097
$45.91
Time Remaining: 5d 6h 31m
Buy It Now for only: $45.91
Bachmann On30 Scale Train Box Car White Pass  Yukon 27001
Bachmann On30 Scale Train Box Car White Pass Yukon 27001
$45.91
Time Remaining: 5d 6h 31m
Buy It Now for only: $45.91
Bachmann HOn30 Scale Narrow GaugeTrain Box Van Blue 77202 Thomas
Bachmann HOn30 Scale Narrow GaugeTrain Box Van Blue 77202 Thomas
$48.17
Time Remaining: 5d 6h 35m
Buy It Now for only: $48.17
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 315 nd
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 315 nd
$64.16
Time Remaining: 8d 21h 56m
Buy It Now for only: $64.16
HAWTHORNE VILLAGE On30 BACHMANN CONFEDERATE CIVIL WAR J E B STUART BOX CAR 005
HAWTHORNE VILLAGE On30 BACHMANN CONFEDERATE CIVIL WAR J E B STUART BOX CAR 005
$59.99
Time Remaining: 14d 9h 25m
Buy It Now for only: $59.99
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 3145 n
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 3145 n
$64.16
Time Remaining: 15d 18h 10m
Buy It Now for only: $64.16
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 605
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 605
$64.16
Time Remaining: 18d 20h 50m
Buy It Now for only: $64.16
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3470
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3470
$45.00
Time Remaining: 21d 9h 29m
Buy It Now for only: $45.00
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3262
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3262
$45.00
Time Remaining: 21d 9h 31m
Buy It Now for only: $45.00
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3146
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3146
$45.00
Time Remaining: 21d 9h 41m
Buy It Now for only: $45.00
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3438
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3438
$45.00
Time Remaining: 21d 9h 44m
Buy It Now for only: $45.00
ON3 ON30 SILVER CITY MODELS DRGW 1872 12 4 WHEEL BOX CAR KIT
ON3 ON30 SILVER CITY MODELS DRGW 1872 12 4 WHEEL BOX CAR KIT
$36.00
Time Remaining: 22d 21m
Buy It Now for only: $36.00

Other On30 Scale train items recently purchased through this site:

ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3438
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3262
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3470
ON30 AMS 3000 Series Box Car Denver and Rio Grande Western DRGW 3146
On30 Fat Albert Boxcar Conversion to fit Bachmann 18ft flat car
Bachmann On30 Scale Train Box Car Oxide Red Data Only 27097
A Plan For VIctory Box Car Hawthorne Village Civil War Confederate Express NEW
Stonewall Jackson Box Car Hawthorne Village Civil War Confederate Express NEW
Bachmann On30 Scale Train Box Car South Pacific Coast Sunset Logo 27002
A Plan For VIctory Box Car Hawthorne Village Civil War Confederate Express MIB
Bachmann On30 Scale Train Box Car White Pass Yukon 27001
Bachmann On30 Scale Train Box Car Mineral Red Data Only 27098
Bachmann On30 Scale Train 18 Freight Cars Box Car 2 per box 26501
ON3 ON30 SILVER CITY MODELS DRGW 1872 12 4 WHEEL BOX CAR KIT
Bachmann On30 Scale Train 18 Freight Cars High Gondola 2 box 26541
Bachmann On30 Scale Train 18 Freight Cars Low Gondola 2 box 26531
Bachmann On30 Scale Train 18 Box Car W Murphy Roof Gray 2 box 26553
HAWTHORNE VILLAGE On30 BACHMANN CONFEDERATE CIVIL WAR J E B STUART BOX CAR 005
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 315 nd
Bachmann HOn30 Scale Narrow GaugeTrain Box Van Blue 77202 Thomas
JEB Stuart Boxcar Hawthorne Village Civil War Confederate Express MIB
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 606
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 3145 n
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 605
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 603