oldblue49,
Did you look at old posts about radial tires, because I think a lot of brands that have 6 ply LT radials have been reported by various people. I got 6 ply LT radials from Cooper tires that fit on the original rim just fine (@ about $100 installed, plus tube).
As I recall from reading magazine ads, Coker/Goodrich/Goodyear have bias tires (Coker is a little expensive).
What lines/brands of tires are available near you?
Tim