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'.

On3 On30 WISEMAN MODEL SERVICES RIO GRANDE SOUTHERN DRAG FLANGER 01 KIT RGS
On3 On30 WISEMAN MODEL SERVICES RIO GRANDE SOUTHERN DRAG FLANGER 01 KIT RGS
$59.95
Time Remaining: 36m
Buy It Now for only: $59.95
On30 SPEC 2 6 0 STEAM SOUND MODULE BAC44957 NIB NEVER OPENED
On30 SPEC 2 6 0 STEAM SOUND MODULE BAC44957 NIB NEVER OPENED
$116.10
Time Remaining: 3h 52m
Buy It Now for only: $116.10
Namib Narrow Gauge Sydney M Moire HT Crittenden
Namib Narrow Gauge Sydney M Moire HT Crittenden
$86.81
Time Remaining: 4h 59m
Buy It Now for only: $86.81
Ride the Sandy River Americas Largest Two foot Railroad Narrow Gauge
Ride the Sandy River Americas Largest Two foot Railroad Narrow Gauge
$47.02
Time Remaining: 5h
Buy It Now for only: $47.02
Twenty Four Inches Apart The Two Foot Gauge Railways of the Cape of Good Hope
Twenty Four Inches Apart The Two Foot Gauge Railways of the Cape of Good Hope
$47.02
Time Remaining: 5h 3m
Buy It Now for only: $47.02
On3 On30 O CRAFTSMAN RAGGS RIO GRANDE SOUTHERN PLACERVILLECO DEPOT KIT NEW
On3 On30 O CRAFTSMAN RAGGS RIO GRANDE SOUTHERN PLACERVILLECO DEPOT KIT NEW
$329.95
Time Remaining: 8h 25m
Buy It Now for only: $329.95
Micro Engineering On30 10 140 ON 2 1 2 NON WEA CODE 70 BIGDISCOUNTTRAINS
Micro Engineering On30 10 140 ON 2 1 2 NON WEA CODE 70 BIGDISCOUNTTRAINS
$43.45
Time Remaining: 14h 52m
Buy It Now for only: $43.45
Busch 12379 Hof Eimerkettenbagger  New Original Packaging
Busch 12379 Hof Eimerkettenbagger New Original Packaging
$62.35
Time Remaining: 1d 7h 35m
Buy It Now for only: $62.35
Campbell Models 426 Kiowa Trackside Details 2 HO kit
Campbell Models 426 Kiowa Trackside Details 2 HO kit
$27.00
Time Remaining: 1d 8h 3m
Buy It Now for only: $27.00
Scale Model Masterpieces Yorke Logging Camp Cook House Kit HO
Scale Model Masterpieces Yorke Logging Camp Cook House Kit HO
$61.36
Time Remaining: 1d 8h 18m
Buy It Now for only: $61.36
On3 On30 O CRAFTSMAN RAGGS RIO GRANDE SOUTHERN PLACERVILLECO DEPOT KIT NEWb
On3 On30 O CRAFTSMAN RAGGS RIO GRANDE SOUTHERN PLACERVILLECO DEPOT KIT NEWb
$329.95
Time Remaining: 1d 8h 26m
Buy It Now for only: $329.95
Logging Truck custom built O scale On30 lot 2
Logging Truck custom built O scale On30 lot 2
$148.00
Time Remaining: 1d 11h 42m
Steam Tractor Logging Diorama custom weathered handcrafted O scale On30
Steam Tractor Logging Diorama custom weathered handcrafted O scale On30
$175.00
Time Remaining: 1d 11h 42m
O Scale On30 Logging Truck custom weathered top eye catcher lot 8
O Scale On30 Logging Truck custom weathered top eye catcher lot 8
$148.00
Time Remaining: 1d 11h 42m
On30 Steam Locomotive Switcher + Car TSU DCC  Sound custom weathered
On30 Steam Locomotive Switcher + Car TSU DCC Sound custom weathered
$384.00
Time Remaining: 1d 11h 42m
On30 Logging Steam Donkey custom weathered metal wheels lot 2
On30 Logging Steam Donkey custom weathered metal wheels lot 2
$165.00
Time Remaining: 1d 11h 42m
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: 1d 11h 42m
O scale or small 1 24 G scale Logging Truck custom weathered lot 0
O scale or small 1 24 G scale Logging Truck custom weathered lot 0
$146.00
Time Remaining: 1d 11h 42m
Historic Logging Truck custom weathered handbuilt O scale On30 lot 5
Historic Logging Truck custom weathered handbuilt O scale On30 lot 5
$148.00
Time Remaining: 1d 11h 42m
Legendary TEE Express Engine made by Fleischmann strong puller smooth runner
Legendary TEE Express Engine made by Fleischmann strong puller smooth runner
$76.00
Time Remaining: 1d 11h 42m
O or On30 scale Historic custom built and weathered Logging Truck lot 22
O or On30 scale Historic custom built and weathered Logging Truck lot 22
$138.00
Time Remaining: 1d 11h 42m

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Peco SL 500 On30 Narrow Gauge Mainline Plastic Tie Flex Track Code 100
NEVADA CENTRAL Sagebrush Narrow Gauge Out of Print NEW BOOK
On30 Backwoods Miniatures RTR brass 2 6 2T Narrow Gauge Steam Loco Bachmann
ON30 MICRO ENG TRACK
bachmann spectrum 28671
Seven 7 New in Box Building kits by FinestKind Models NIB S Scale Sn3
Group of Three S Scale Building KitsTown BusinessesNew in BoxSn3
Four 4 S Scale Building Structure KitsNew in BoxNIBS ScaleSn3
AHM Minikits Narrow Gauge Engine Shed Weathered Painted and Lighted
Three 3 building kits from banta modelworks RGS NIB S Scale Sn3
Narrow Gauge LOMBARD Log Hauler Finished Model HOn3 HO Scale Craftsman model
Micro Engineering 12 138 On30 Code 83 36 Weathered Flex Track Pack of 6
Hangman Creek Lumber Company DVD HO HOn3 S Sn3 O On3 On30 Narrow Gauge
Two S Scale Residence kits Laser kits New in Box NIB Sn3
BTS 17143 On30 Laser Cut Narrow Gauge Cheat Run Trestle Craftsman Building
HO HON3 PROFESSIONALLY BUILT TEN STAMP MILL FINISHED MODEL
BACHMANN 44957 On30 SPECTRUM 2 6 0 STEAM SOUND MODULE
HO HON3 CUSTOM BUILT FROM SCRATCH DOLLY VARDON MINE FINISHED MODEL
Bachmann Spectrum 27301 On30 Assembled Steam Log Skidder Non Operating
Group of eight 8 Sn3 Logging Disconnect Bunk cars S Scale Ready to Run