How cheap? I mean, what's your budget? And more importantly - what size?
I'm just about to complete a refurb of a 57x57cm 1979 Motobecane with Shimano 600 drivetrain and Weinmann brakes.
On the other hand, I'm also refurbing a 50x48.5cm Swiss Record with Shimano 600 6207 top to bottom - 9/10 condition!
And then next in line for a build is a lightweight 56x57cm Jan Janssen Vitus 979 with full Shimano 600 Tricolore and Phil Wood wheels.
Does any of that sound interesting?