Tim, I had that setup you have years ago with great results. Original rims with radials are just fine, but the caveat is that it's not optimal, nor is it what the engineers of radial tires recommend. But, if you have the rims already, and you want radials, and the tire supplier will put them on those rims, have at it.
If you need rims, get disc brake compatible ones (in case you get hit on the head and decide you want front disc brakes) and radial compliant ones. I think I went 10 years on the stock rims with radials.
