Found this lock plate last week and finally got around to cleaning up. I found amongst fur trade items so assuming it is within that period range. Any help would be appreciated.
Very nice lock! It appears to be an English Ketland lock (at least of that style) but unfortunately I'm sure the markings are gone. I would put it as late 18th century.
The lock is missing the tumbler, sear, sear spring, the main spring and hammer as well as the screws that held those parts in place, that's why you see the holes. Excellent find, even with the missing parts.