I seem to recall a Crown Zellerbach car or two shoved off at the end of a spur on the Sumpter Valley. They said the cars kept derailing and were not really usable for them.
I think Stathi Pappas has a flatcar still available, in storage located in Roseville CA.
Other flatcars were also located on the private ranch RR near San Luis Obispo.
I found this locomotive (and perhaps a second behind it) for sale on D.F. Barnhardt. Location: Wisconsin... where?
36" Gauge electric locomotive
I'm curious about what is preserved, and where.