Where to buy correct alternator for a 1969 340 swinger non a/c car

Lack of rebuildable cores is the problem. I don't see any roundbacks at Napa or O Reilly. None listed at Autozone either. Edit: I best look back at O Reilly. Rusty said they have some listed.
Damn I was wrong. I must have looked up one for my 70. I didn't find the DL7014 at Autozone that 12many found and the R111598A that O reillys has listed that Rusty found. I was looking for something lower amp than 55. Damn, I feel bad for the wild goose chase.