hey guys, I need some help. where can I get a less expensive upper for a AR15, the lower (stripped) and a bolt and bolt carrier. can anybody point me in the right direction. dont hate me but if I can come up with all of that stuff I have a friend who will build me a AR 15. he has all the rest of it I can have for free. the barrle has only seen 200 rounds the rest is new. I really want to get it all together for him.