I've been thinking along the same lines out here in NJ to go with my Porter fireless. There is a standard gauge bobber frame that is for sale up in Danbury. I was interested in only the pedestals, boxes, and springs but the concern is that they may be way too big. I have not had time to go up for a first hand look. The POC for that frame is
jmpoor3171@yahoo.com
If you pm me at
jrmay@monmouth.com I can send you pictures of the frame. Its from a PRR bobber.
J.R.