I came across a few odd looking locos and some neat trams that might scale down well to the 15 inch gauge, and this tram stole my modelmaking heart
Cuban Brookville for Scott
The rest can be seen in these pages -- be warned this might distract you for a while if you haven't already been there.
An open air passenger:
A grass burner:
Another open air railcar:
And another tram that looks great:
A neat loco that is just crying out to be converted to 15 inch guage: