Got a free Cooper frame set, now what do I do? It has 939 stamped on the BB.

I currently ride a commuter with an IGH. I've ridden derailleur bikes but never worked on one. I'd like to get this one going but don't really know where to start.

My budget is $500. Do I get original parts? Modern parts? Can I get a road bike off of CL and swap it out? Any suggestions welcome.