Looking for some help to try and get some kind of a reasonable value of my Colt AR-15 A2 HBar Sporter I don't have the box for it but still have the manual that came with it. It has a few minor marks on it but is in overall pretty good condition. It has been used and enjoyed but not an excessive amount of rounds put thru it. Last 10 years it has been basically sitting in the safe. I may decide to sell it if it has a decent value, if not will just keep it. Have looked on-line but really can't put my finger on a fair price. Best I can tell it was manufactured about '84-85. The manual has a date of 1985 on it. The serial # is a 6 digit# Starting with SP 23. Any help, advice, opinions are welcome. Thanks in advance.