My disclaimer is that I am not very knowledgable about scale geared locos. However, the only one I have ever seen was imported by Westside Model Co. and the box/ad said it came with both standard gauge and 3ft narrow gauge trucks. I have seen a few of these at various shows. Generally they have been without the box and only one or the other set of trucks. I don't remember who was listed as the mfg/builder.
I am pretty sure the prototype was listed as Westside Lumber Co.
These came unpainted. someone could have taken the Westside model (as opposed to Westside Lumber prototype), and detailed it to something they wanted and then painted it. That would be my first guess.
