Anyone living in Carlisle would not have that far to go to York to get a gun.
The Kentucky Rifle Association has a lot of CDs of longrifles from different areas. Not expensive and they have great pictures. In volume 2 of RCA, #92 is a big hoss of an early gun - not giving ground to Albrecht, Dickert, or Schreit early rifles in mass of the buttstock. It could easily predate 1770. There’s an early Schroyer with an unusual patchbox latch not shown in RCA but it might be on the CD. Not enough early York rifles are made by contemporary makers.