That is an odd creature! With it's looks and the gauge, it certainly doesn't look like something from the North American continent.
If I had to guess where that was from , I might guess that it was from India. I have seen some pretty strange looking railbusses that were built there. It is a shame the photo is cropped so close that there are few visual clues.
I love stuff like this, and have built or modified three railbusses, one in Ho, one in HOn3, and one In G scale. I have a NWSL flea drive, and some parts on order to build another in HOn3. I have a Jordan Miniatures Mack railbuss that I am going to power and modify
Bill Nelson