Like others have said, AR prices have been berserk for a few months now, Century Arms makes (assembles rather) just the rifle you're looking for using Colt parts. They're not known for being the highest quality manufacturer but usually they make good shooters and Century has good customer service and will fix most any problem a rifle comes with.
Edit- posted a bad link
LCpl Williams, Evan T. USMC-R, 02-08-2010 ~
D Co, 4th CEB, Engineers UP!! OEF 21JUN-20SEP2011
REV. 19:11 And I saw heaven opened, and behold a white horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war.