[Dave]

I've seen the van radios over a few years ago now at swap meets in unknown or untested condition sell anywhere from 200-250 range. In working condition the price goes up from there. The problem is, the parts to fix them aren't readily available as are the people with the knowledge to fix them.
Having a working radio is obviously a better starting point. However, even then that's not a guarantee that a 40 plus yr old electronic device won't develop a problem suddenly, this I know.