At 74, I wouldn't be shooting iron sight handgun silhouettes without my Merit eyeglass iris. I recently took up lever action silhouette and my guns all wear Williams receiver sights or Marble tang sights. I have a Merit iris device on the 22 and need more for the other rifles. THERE ARE NONE! Everybody is out and most say no backorders. Are they out of business? Have they gone the way of BoMar sights, never to be seen again? I found the Snover Hadley eyegups, but there is no room for one on a receiver sight.