I have a handful of factory Colt M4 Barrels. These all LOOK new, but I believe that they are fired, and then cleaned up or refinished. They are in excellent condition. I've gauged a few of them, and they all gauge like a brand new barrel, they do show tell tale signs of being fired previously. I'd be shocked if these had more than a few hundred rounds through them.
Price is $299 each. Please add $15 for shipping, and $10 if you want to use Paypal. Of course, if you get one and you think it's a haggared old piece of rebar, I'll gladly take refund money upon it's return (you pay to ship it back).
These are 14.5 inch, 1/7, chrome lined factory Colt M4 Barrels, but they are not the SOCOM profile.