This was for Pioneer I-II-III/Silverliner II Budd-built cars only. No St. Louis cars, no Metroliners here. (Although if these do well, i might consider putting together an order for those later.)
As i recall from my discussions with the builder, the minimum order needed to make the run happen was about 10 cars, at $250 each for a shell and some other parts. This price does NOT currently include the mechanism or assembly, although that might be somewhat negotiable for a slightly higher price.