Folks, Young master Idrach is now a cadet and is having to deal with the Mk8 rifle. He's having problems (being about 4 stone, holding the weapon steady is clearly one of them so he's gone onto weight training ), also a bit of marksmanship training is in order. However, that means that the optics have had to come off my .22 and he's not entirely convinced about the notch rear sight that has gone back on. I can find new air rifles with diopter rear sights for about £70 (frankly, if this is the option, I'm not going to weep about it) - does anybody know where I can get a decent pinhole rear sight from - web, Edinburgh, Stirling or Weegie-ville - please? The gun is a bog-standard Weihrauch HW-77 on the unlikely chance that makes any difference ... Ta much.