English lock is from the 1815-1840 era. Lock was rebuilt somewhere around the 1970's using Russ Hamm parts. The Russ Hamm parts are appropriate for the lock and are a good match. Lockplate is the original and is typical of the English locks of the era. Lock is in good working order and sparks. These locks stopped being shipped to America around 1840, so this suggests the rifle is pre-1840. The long graceful curve of the stock is similar to the rifles of Bucks County (a distinct style within the Lehigh Valley school of rifle making), but this is only a guess. Ramrod is not original.