Almost everything about the K's that is "on-line" is wrong. The K's never made locks. They sold locks, tens of thousands of them, but they were all made in the Birmingham trade. In fact, it would be reasonable to presume that no British gunmaker after the first quarter of the 18th century, and likely earlier, made their own locks although some of the better makers may have finished them. In any case, when the post-revolutionary importation of British locks is firmly fixed by the arms embargo that was instituted in 1774 and lifted in November of 1792. The K's were one of the first to take advantage of this - theirs was the second or third export license granted but the export of loose locks didn't begin until a little later. A Ketland lock made prior to the embargo would not have been marked on the inside. I've had a couple of those locks, one on a gun actually dated 1793 and probably one of the earliest export fowlers.
I'd be able to give you a better analysis if I could see the photos.