Those were sold by the CMPicon years ago (13 ~ 14 yrs?) for $70 for the better grade ones. I had three and sold one for about $250?? Still have two. They were used mostly or maybe only by the USNTS' in boot camp. I've seen pictures of the guys practicing with them at the Great Lakes Naval Training Center in one of their yearbooks. Pretty cool! 1942 ~ 1943. Early one had Lyman Peep sites and later on they switched to their own Mossbererg "Microclick" peeps.