The close-up lock photo shows three screws that are modern made on a "love machine", sear screw, sear spring screw and tumbler/cock screw. Cock is investment cast.
In my ever-so-humble opinion as a metallurgist involved in some manner of manufacturing since JFK was having fun in the White House pool. Also been messing with modern muzzle-loaders since Ike was on his way out.
Can't say about the rest of the gun but I am older than that lock.