Thanks all...my first enquiry was to coltparts, they only have a screw avail.
Dixie list some as well as Brownells but I haven't enquired yet if the foreign shipping tax has been paid to the US govt.
This old girl has been quit an adventure. Very rusted/abused condition when I got it (was used as a hammer to drive fence staples by the previous owner). The cylinder and base pin was seized to the frame. I tried pressing pin out with a 20 ton press but no joy so ended up drilling the pin out of the frame from both ends so I could remove the cyl. from the gun (very carefully drilled/milled the pin until only a foil thickness remainded and got real lucky with that operation, didn't even touch the frame holes at either end). After getting the cyl out it was easier to brace properly and ended up getting the bushing to press out without damaging the cyl..
Still needs a lot of cleanup and the parts mentioned but surprisingly the chambers and rifling are in very good shape, no pitting to worry about at all.
My plan is, if I can get her mobile again, to shoot a cowboy match with my 2 1st gen colts both considerably over 100 yrs old (along with my ca. 1892. 32-20)