This model is famous in its own right, as I recall, as one of the first models made in resin.  As an O scale model, it was a good show piece, and I recall it being exhibited at Naperville in fairly recent years.  Don't recall who owned it at that time.  In that sense, it didn't really need a prototype, as it was intended to show off the dramatic things that could be done with resin casting.  Sorry I can't be much help with the actual question.

Ron Merrick