I just purchased my 1st Ar15, it is a Colt Match #6551 with 20" barrell and carry handle. I know that I want to put a 6 position stock on it but not sure about what else. I will mainly use it to target shoot with, but this is my only rifle for now so if I get the chance to go hunting, this will be the gun for now! I don't know if I should put a scope or red dot. I would love to have a "nice" optic now, but I just paid for the rifle so the funds are low. I will get something "nice" later but for now I need to stay at $100 or below for my optics. Any upgrade suggestions would be very helpful. Also will most after-market parts fit on my Colt? Thanks in advance for the help!!