Ron if you can not find a shop to install a new core up your way call Active Radiator (214)462-7855 I haven't used them but a friend said they were good.

However for a different look at this, I bought a 3 core aluminum radiator about 8 or 9 years ago and it has been just fine. The tank and bottom are heavier aluminum than I expected. I bought it on Amazon and at that time I think it was around $115 delivered. For something like $30 more I could have had 4 row but I figured 3 would be okay. None of the radiator shops around here at that time said they could fix my old one using brass and copper for anywhere less than $300 and one place said $500. So that's kind of a ballpark. I don't know what they would charge today. The one shop in Dallas that I had used in the past closed a few years ago. I have a 1951 GMC radiator in the attic. I had it re-cored around 1985 using the old style core and it was leaking when I gave up on it. Rather than find the leak and fix it, I decided the same thing you are thinking...another leak is just waiting to happen. Besides that I can't tell the aluminum one runs at any different temperature and as you know Dallas in the summer is like the waiting room for hell. Good luck!

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end