jls
What little data I could find on this round comes from the Lyman 45th Edition manual . ( old data so start low and work up )
180 grain JSP
Unique - 10 to 11 grains / 1501 to 1587 FPS
2400 - 17 to 19 grains / 1597 to 1793 FPS
IMR 4227 - 17 to 19.5 grains / 1400 to 1751 FPS
171 grain cast w/ GC
Unique - 12 to 12.5 grains / 1692 to 1751 FPS
2400 - 17 to 19 grains / 1861 to 2020 FPS
IMR 4227 - 17 to 19.5 grains / 1658 to 1904 FPS
As for bullets , Buffalo Arms sells the 180g jacketed @ $43.00 per 100 , for cast you may be able to find a used mold on e-bay or one of the other auction sites . Another way may be to have a standard cast bullet in the 180 to 200 grain range sized down to what you need .
stimpy