I think that you are not the only one who realizes that he is asking for NON Aluminum.
I do not know what year radiator brokenhead is looking for.
But, I did not know that US Radiator, recommended by Denny, has stopped making 47-55 (48-54) Chevrolet 1/2-3/4 ton truck copper/brass radiators?
http://www.usradiator.com/chevrolet-truck-1948-54-6-cyl-radiator.html