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'.

Stoney Creek Designs On30 24 Boxcar Kit RS 004 New Collectable
Stoney Creek Designs On30 24 Boxcar Kit RS 004 New Collectable
$58.99 (14 Bids)
Time Remaining: 1d 11h 15m
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: 3d 14h 52m
Buy It Now for only: $59.99
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
$64.52
Time Remaining: 5d 3h 23m
Buy It Now for only: $64.52
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
$64.52
Time Remaining: 12d 23h 37m
Buy It Now for only: $64.52
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
$64.52
Time Remaining: 16d 2h 17m
Buy It Now for only: $64.52
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 606
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 606
$65.04
Time Remaining: 24d 22h 50m
Buy It Now for only: $65.04
JEB Stuart Boxcar Hawthorne Village Civil War Confederate Express MIB
JEB Stuart Boxcar Hawthorne Village Civil War Confederate Express MIB
$32.99
Time Remaining: 26d 13h 50m
Buy It Now for only: $32.99
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
$64.52
Time Remaining: 27d 7h 23m
Buy It Now for only: $64.52
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: 28d 7h 22m
Buy It Now for only: $64.99
Spectrum On30 27023 Colorado  Southern Boxcar w box foam liner C 7 Nice
Spectrum On30 27023 Colorado Southern Boxcar w box foam liner C 7 Nice
$40.00
Time Remaining: 30d 15h 33m
Buy It Now for only: $40.00
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: 31d 8h 53m
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: 32d 11h 57m
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: 32d 11h 57m
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: 32d 11h 57m
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: 32d 11h 57m
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: 32d 11h 58m
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: 32d 11h 58m
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: 32d 11h 58m
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: 32d 11h 58m
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: 32d 12h 2m
Buy It Now for only: $48.17

Other On30 Scale train items recently purchased through this site:

On30 Fat Albert Boxcar Conversion to fit Bachmann 18ft flat car
Bachmann On30 Scale Train Box Car Mineral Red Data Only 27098
A Plan For VIctory Box Car Hawthorne Village Civil War Confederate Express MIB
Bachmann On30 Scale Train Box Car Oxide Red Data Only 27097
Bachmann On30 Scale Train Box Car South Pacific Coast Sunset Logo 27002
Bachmann On30 Scale Train Box Car White Pass Yukon 27001
Spectrum On30 27023 Colorado Southern Boxcar w box foam liner C 7 Nice
Bachmann On30 Scale Train 18 Freight Cars Box Car 2 per box 26501
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 On30 Scale Train 18 Freight Cars High Gondola 2 box 26541
Bachmann On30 Scale Train 18 Freight Cars Low Gondola 2 box 26531
BINKLEY KIT BUILT HOn3 NARROW GAUGE DENVER RIO GRANDE DRGW BOX CAR WAGON 3145 n
JEB Stuart Boxcar Hawthorne Village Civil War Confederate Express MIB
Stoney Creek Designs On30 24 Boxcar Kit RS 004 New Collectable
Bachmann HOn30 Scale Narrow GaugeTrain Box Van Blue 77202 Thomas
BINKLEY KIT BUILT HOn3 NARROW GAUGE DSPPRR DENVER SOUTH PARK REEFER BOX CAR 606
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