It's a perfectly conventional Birmingham export lock - one of the lest expensive described as "common fence gunlocks hardened & engraved." I've had examples that had the K name on the inside but were not marked on the outside. Regardless of who imported it, they were all made in the B'ham trade. The evidence I've gathered suggests that this trade did not begin until at least 1792. Prior to that, all arms and "military stores" were embargoed by order of the Privy Council. The gun itself is a typical, very plain NE fowler. The long wrist and deep flutes in the stock suggest to me a date between 1792 and 1800 and probably closer to the earlier date.