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

Model railroad 1203 scale Narrow gauge LS Caboose DRGW detailed interior
Model railroad 1203 scale Narrow gauge LS Caboose DRGW detailed interior
$200.00
Time Remaining: 4d 2h 50m
Buy It Now for only: $260.00
On30 Model Railroad Building Built  Painted On30 Narrow Gauge Blacksmith Shop
On30 Model Railroad Building Built Painted On30 Narrow Gauge Blacksmith Shop
$100.00
Time Remaining: 15d 1h 33m
Buy It Now for only: $100.00
On30 Model Railroad Hotel Built Finished Lighted Narrow Gauge Model Railroad Bld
On30 Model Railroad Hotel Built Finished Lighted Narrow Gauge Model Railroad Bld
$120.00
Time Remaining: 18d 14h 34m
Buy It Now for only: $120.00
HO Scale standard Narrow Gauge MODEL FORD INSPECTION CAR K129B KIT SSLTD
HO Scale standard Narrow Gauge MODEL FORD INSPECTION CAR K129B KIT SSLTD
$51.30
Time Remaining: 19d 13m
Buy It Now for only: $51.30

Other On30 Scale train items recently purchased through this site:

Model railroad 1203 scale Narrow gauge LS Caboose DRGW detailed interior
HO Scale standard Narrow Gauge MODEL FORD INSPECTION CAR K129B KIT SSLTD
On30 Model Railroad Hotel Built Finished Lighted Narrow Gauge Model Railroad Bld
On30 Model Railroad Building Built Painted On30 Narrow Gauge Blacksmith Shop