Thank you for those responses. For some reason it was beyond me to check the library labels. There is something awesome about that track, this mix of styles, the funky and quirky melody, the drum breaks. It's a beautiful potpourri, but I am also usually a purist -- If it's mono, then taking a later-made stereo version is... off if you get what I mean.
I know this is somewhat of a strange question now, but do you think I should go with the mono version because it's the "real" thing or take the stereo versions and tag it as 1972? I mean, that is probably what it supposed to sound like if stereo was an option (if that was no option. I dunno, I am just guessing here. The version on Youtube is mono, but the crackles and surface noise is in stereo, so it's not the guy's setup).