Bendorsey has a Ma & Pa (Maryland & Pennsylvania) doodlebug on the DLS...somewhere (I tripped over it in CM3.3 whislt looking for some bridges I could use on some of my layouts), but I'll be damned if I can't remember what it's called. In addition, I know there's a McKeen Car by whitepass (somewhat older model, textures are kinda wonky) and 2-3 reskins by cincysouthernrwy...but those are all in NYS&W colors if I'm not mistaken. Your best bet is to look up Ben's model: I'm assuming you're wanting this for the Frisco High Line, and if I rememeber correctly the model can be renamed/numbered like his TOTC/Harriman car sets.
(PS: be warned though, the Ma&Pa car has what is quite possibly the loudest and most obnoxious enginesound in trainz, and the horn is a flat, non-looping one chime "blat." Nothing against the model, I love it nonetheless, but it gets annoying after a while.)
PPS: Bendorsey also has at least two cars (can't remember their exact names, it's something like motor car/doodle bug...I know they're numbered 19 and 20 out of the set) that are set to standard gauge and built out of old Harriman cars. like everything else, they can be renumbered and relettered on a whim.