I got the Colt/Rem Rand (in the pics) back and what the owner says is the barrel it came with. the only mark on the barrel is a "c" in a box. Most came with the COLT .45 AUTO on the barrel so I wasn't sure. I did some searching and colt did use the "c" in 1945. Perhaps this was used when they reworked this 1911?

The barrel has been in his tool box in the hot humid garage in Florida for 10 years but it cleaned up nicely. The only problem I see is it has been internally threaded at the muzzle by the guy with the tool box (a guy that doesn't have a collectors mind if you know what I mean).
He did think that maybe he should have used the series 70 barrel for his shall we say experiment. I'm working on him.