I keep asking for help on this site cos I know nothing!! but I'm trying to learn. As well as problems with the sear, I've now found that the back sight on my Service .177 is wedged in place with silver foil - without it the sight is loose in the dovetail. How should it be held in, is there usually a spring? Also where would I get a replacement sear for this rifle? I would greatly appreciate some advice please.