I thought I had seen a plaque inside the car that said that it was built by Paulaski (spelling?) of City of Industry, CA. He was also into live-steam and had a live steam railroad in the Pearblossom area which I think still exists.
The first issue of the old "Live Steam" magazine that I saw had an article about Paulaski's live steam operation. As I recall the article said that Paulaski had built the passenger car bodies for the RC&BT. A neighbor of my parents was acquainted with Mr. Paulaski.
Of course, I'm thinking about the original equipment of the 1960s.
Brian Norden