A risqué comic play on words on a good man is hard to find.

The Oxford Dictionary of Comic Quotations attributes this to Mae West (1892 - 1980). It's certainly in her style, although I can't find any source documentation to support the attribution. Which part of the man she preferred to be hard I'll leave to your imagination.

Another artist who could plausibly have coined the quip was Sophie Tucker ('The last of the red-hot mammas'), who used a good man is hard to find as her signature tune.