Classics Library published a number of exploitation titles in the late 60's. Unfortunately, the title of this particular line makes electronic searching a challenge and I don't know much about them. If you know anything about these books, please drop me a line.
Viceroy Books were another great publisher in the late 60s. Their books usually feature solid cover art. The titillating titles of Viceroy Books come with the promise the standard "shocking true stories" of the then-current sexual zeitgeist.