hello,i believe that an old army has the same internals as a blackhawk.i've had very good luck just polishing the sliding surfaces internally.no real metal removal just polishing with a dremel tool & a very fine polishing rouge.this smoothed up the trigger so much that it feels like the trigger is on bearings.if the trigger pull weight is objectionable you can always put different springs in it.a good source for all gunsmithing tools/parts is BROWNELLS.their catalog is like a big kids wish book!can't help w/the clone,sorry.
good luck & have fun!
good luck & have fun!