for followcams, definitely don't do the FD lens. They're alright for screwing around with, and I have an adapter for mine that actually ended up working out pretty well, but it just turns the lenses into total tele-length and makes them very soft wide open - cool for a dreamy effect but definitely not the best for followcams. I only use them for messing about.
If you're really looking for vintage glass, maybe try the zenitar 16mm f2.8 or the tokina/vivitar 17mm f3.5?
From what I remember, both of those could be had in the 175$ range or so... If you're using them at anything below f5.6 or so, they're pretty bad, but above that and they're actually quite sharp I hear. Still, I'd go for something like the rokinon/sangyang 8mm f3.5 fishy.
Have a nice day, Bluename.