If you can get for the right price and its in good shape, go for it, they can be adapted to anything, Paxton is the same thing, I don't know about parts availability for the early stuff, but the only thing that gets replaced commonly is seals and bearings.
Most I've seen or used were blow thru style. just mount fabbing and a carb box, the rest is sheet metal tubing.
A friend of mine is building a 32 Lo-boy (Speedway) with a flattie in it and is using a charger from the late model Buicks on it. Looks very neat with the throttle body at the rear of the s-charger.