Just go to a reputable radiator repair shop that you trust, and get them to prsssure test it. The numbers won't lie. You might get lucky and just have to paint it. (I'd say it'll probably have to be rebuilt if you wanted to guarantee reliability)
Daryl
Ya, what they said! LOL I had my original 66 radiator checked and repaired. It needed 2 small leaks repaired and boiled out. Cost me about $60. It's good to go now! Mike