I have some what of a "frankin FAL" built on a Century reciever. Its a metric. Can I use any metric parts on this riffle? Had it for 7 months now about 900 rounds of multipul kinds of ammo, both .308 and 7.62x51 and not one problem. im also looking for any kind of parts people are willing to sell. When fit hits the shan i'd like to have some spares. thanks guys