I found a lock from an Ultra-HI Harpers Ferry. With a little carving and filing on the lock mortice it should fit. The lock is a cheaply made one, but it beats no lock at all. The Kentucky is a 50 cal. when I get the funds I will have it bored out to a 54 cal. smoothie. In this part of PA 50 yds. is about the maximum shot for deer. I get more use out of a smoothbore for small game.