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

Roy C Link Industrial Narrow Gauge Handbook 7mm O 14 model railways RARE 
Roy C Link Industrial Narrow Gauge Handbook 7mm O 14 model railways RARE 
$73.07
Time Remaining: 4h 31m
HO Gauge Bachmann White Pass  Yukon Set
HO Gauge Bachmann White Pass Yukon Set
$289.99
Time Remaining: 11h 21m
Buy It Now for only: $289.99
Rails Neath the Palms 1st Edition 1983 by Robert Mann Hardback Gd Con Cover Iss
Rails Neath the Palms 1st Edition 1983 by Robert Mann Hardback Gd Con Cover Iss
$37.99
Time Remaining: 14h 24m
Buy It Now for only: $37.99
O SCALE On3 On30 BANTA MODEL WORKS 6131 BO Hotel
O SCALE On3 On30 BANTA MODEL WORKS 6131 BO Hotel
$94.00
Time Remaining: 14h 52m
Buy It Now for only: $94.00
HO Farm Wagons 2 pack 2501
HO Farm Wagons 2 pack 2501
$25.68
Time Remaining: 15h 19m
Buy It Now for only: $25.68
O SCALE On3 On30 BANTA MODEL WORKS bmw 149 O The Stock Pens
O SCALE On3 On30 BANTA MODEL WORKS bmw 149 O The Stock Pens
$138.00
Time Remaining: 17h 52m
Buy It Now for only: $138.00
Logging Camp Cook House Kit Scale Model Masterpieces Yorke Fine HOn3 NEW
Logging Camp Cook House Kit Scale Model Masterpieces Yorke Fine HOn3 NEW
$54.95
Time Remaining: 18h 2m
Buy It Now for only: $54.95
Northwest Short Line 28046 On30 Replacement Gear Set for Bachmann Railbus
Northwest Short Line 28046 On30 Replacement Gear Set for Bachmann Railbus
$34.95
Time Remaining: 19h 13m
Buy It Now for only: $34.95
bachmann spectrum 28671
bachmann spectrum 28671
$140.00
Time Remaining: 20h 40m
Buy It Now for only: $140.00
Bemo Schmalspur Bahn
Bemo Schmalspur Bahn
$100.00 (1 Bid)
Time Remaining: 21h 22m
Logging Camp Portable Bunk House Kits Thomas Yorke Scale Model Masterpieces HOn3
Logging Camp Portable Bunk House Kits Thomas Yorke Scale Model Masterpieces HOn3
$44.95
Time Remaining: 22h 19m
Buy It Now for only: $44.95
Historic Logging Truck custom weathered O or On30 scale lot 6
Historic Logging Truck custom weathered O or On30 scale lot 6
$89.00
Time Remaining: 23h 38m
Buy It Now for only: $89.00
Old Ford Logging Truck custom weathered lot 4  O SCALE  ON30
Old Ford Logging Truck custom weathered lot 4 O SCALE ON30
$118.00
Time Remaining: 23h 38m
Buy It Now for only: $118.00
Busch HOF 12341 Points Left  NEW ORIGINAL PACKAGING
Busch HOF 12341 Points Left NEW ORIGINAL PACKAGING
$31.04
Time Remaining: 1d 3h 16m
Buy It Now for only: $31.04
Roco 32403 H0e Electric Light Railway Soft Right New Original Packaging
Roco 32403 H0e Electric Light Railway Soft Right New Original Packaging
$34.09
Time Remaining: 1d 3h 55m
Buy It Now for only: $34.09
BEMO 2250 110 RhB CLOSED WAGON Gterwagen Gb 5090 MINT BOXED mw
BEMO 2250 110 RhB CLOSED WAGON Gterwagen Gb 5090 MINT BOXED mw
$30.01
Time Remaining: 1d 8h 47m
Buy It Now for only: $30.01
TILLIG 85181  INTERSECTION DESTRO FOR TRACK 3 WAYS H0H0e
TILLIG 85181 INTERSECTION DESTRO FOR TRACK 3 WAYS H0H0e
$31.41
Time Remaining: 1d 8h 54m
Buy It Now for only: $31.41
TILLIG 85182  INTERSECTION LEFT FOR TRACK 3 WAYS H0H0e
TILLIG 85182 INTERSECTION LEFT FOR TRACK 3 WAYS H0H0e
$31.41
Time Remaining: 1d 8h 54m
Buy It Now for only: $31.41
TILLIG 85185  TRACK THREE WAYS H0 H0e WITH GEARBOX LEFT SIDE  RIGHT
TILLIG 85185 TRACK THREE WAYS H0 H0e WITH GEARBOX LEFT SIDE RIGHT
$31.41
Time Remaining: 1d 8h 54m
Buy It Now for only: $31.41
TILLIG 85186  TRACK THREE WAYS H0 H0e WITH GEARBOX SIDE RIGHT  LEFT
TILLIG 85186 TRACK THREE WAYS H0 H0e WITH GEARBOX SIDE RIGHT LEFT
$31.41
Time Remaining: 1d 8h 58m
Buy It Now for only: $31.41
On30 Supply  Crew Train Complete Train With Locomotive Custom Built Weathered
On30 Supply Crew Train Complete Train With Locomotive Custom Built Weathered
$550.00
Time Remaining: 1d 11h 1m
Buy It Now for only: $550.00

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Peco LK 555 Narrow Gauge Turntable Turn Table Nickel Silver 0 165 On30 Scale
O On3 On30 WESTERN SCALE MODELS M 1 3 WORKING MINE ORE CARS 2 FIGURES KIT A
O On3 On30 WESTERN SCALE MODELS M 1 3 WORKING MINE ORE CARS 2 FIGURES KIT B
Grandt Line On3 Narrow Gauge Train Railroad Parts Assortment
Peco LK 555 On30 Turntable Turn Table KIT Based on American Armstrong type
Sundance Narrow Gauge Railroad
ON30 RAIL TRUCK CONVERSION KIT PASSENGER CAB FITS BACHMANN RAIL TRUCK
On30 TWO TRUCK CUSTOM BUILT LOGGING LOCO DCC CUSTOM WEATHERED
RIO GRANDE Chasing the Narrow Gauge Volumes I II III By Robert W Richardson
bachmann spectrum on30 NEW 26312 Coach
On30 Bachmann Spectrum Rail Truck 29199 painted unlettered Kadees
2 car set 1203 Scale Narrow Gauge Fall River Gondola flat car
bachmann spectrum on30 NEW 25478 2 4 4 Forney DCC
On30 Bachmann Spectrum 25699 2 Truck Shay lettered painted DCC ready
bachmann spectrum 28498
bachmann spectrum 28671
Bachmann Spectrum 2 4 4 Forney DCC Steam Locomotive On30 25478
bachmann spectrum 28904
Bachmann Spectrum on302 4 4 Forney DCC Sound
Bachmann Spectrum T Boiler Two Truck Shay Steam Locomotive Train On30 25699
Box of 12 Peco SL 600 Flexible 36 Flex Track Code 200SM 32 Narrow Gauge Scale
HOn3 DRGW ROTARY SNOW PLOW KIT BY DURANGO PRESS
bachmann spectrum on30 NEW 25128 Street Car
Durango Press DRGW Derrick Car OP DP 77 On3 Kit
HARTFORD PRODUCTS FOUR T 10 1203 SCALE WEST SIDE LUMBER CO 4 FT TRUCK KITS