Hi, I have to bring my new Bushmaster to the gunsmith for a few installations and stock pinnings that I knew I would when I bought it. I got cute and tried to do a few things myself a few weeks ago and , I knew I shouldn't but I did, and I think I lost a detent from the pistol grip/stock area and also broke a spring, I have the spring but I THINK it's not usable again (of course it's possible I'm wrong,) Now my question is, are these parts interchangable from brands and do average gunsmiths have these types of things? The reason I ask, if I HAVE to I will buy a 5-10 dollar Bushmaster Spring Kit and then a $40 Bushmaster "detent and pin" kit , and bring with and say, here's them all just in case, but if not and the gunsmith should have these all and just take the one spring and one detent/pin he needs from his kit, I'd rather go that way. And of course I also meant to ask, if the Bushmaster springs and detents would be different than other companies/brands springs/pins etc? Thanks much thanks much, Wanna kill these ads? We can help!