I just found the same lock you have and the only differance
is the width. The one I have is 1-3/8 wide the site where I found the lock was also pre civil war.This lock was found in Milwaukee Wisconsin .I also believe this lock to be of civil war era? I found this lock with a metal detector about 5 inches down in a area with large trees all around, one of the few virgin areas left here. I have heard that civil soldiers have roamed this area.