Originally parts for USFA revolvers were 1st made by Uberti under contract by USFA for a short period and assembled in the old Colt plant by USFA. Soon however, USFA acquired the latest CNC machinery, had it installed in the old Colt plant and produced their revolvers from scratch. That's probably where the idea of the Colt equipment came from. But when Colt moved to its new facility, it took its machinery with them to produce their own SAA revolvers.
Doug Turnbull acquired a lot of the parts inventory when USFA ceased production of its revolvers and focused solely on their zip gun product. I have purchased USFA parts from Turnbull and suggest that your friend try there first for a Bisley hammer. If they don't have them, I'd ask Doug if he knows of anyone else that acquired USFA parts.
I just found this site which sells the USFA Bisley hammers from a limited supply that are Turnbull case hardened for $375 each; shown here:
http://tenring.com/?s=bisley+hammer
Ten-Ring Precision, Inc.
1449 Blue Crest Lane
San Antonio, Texas 78232
PHONE: (210) 494-3063
FAX: (210) 494-3066
EMAIL:
[email protected]