I have to go with Mara Corday, for her roles in
Tarantula,
The Giant Claw, and
The Black Scorpion, as well as many B-Westerns and her later roles in several of Clint Eastwood's movies. Intelligent, classy lady who knew how to ham it up with the best of them. I'd love to have seen her in a movie alongside Vincent Price! Quite a looker, too.