Please PM me. You were kind enough to let me have your old duck decoys. I would very much like to send you, as a thank you and free of charge, the BSA 4x32 'scope that I have on the table in front of me. It has, yes, front end distance adjustment from 7.5 yards to infinity. It will come with mounts but, alas, the rear mount clamp and its Allen bolt is knackered. But it will do what you want with a replacement set.