Poster artist?

It was a Creepy or Eerie cover fron the late 60's/early 70's.

Totally a Frazetta swipe. A painting which was also used for Vampira #11.

http://ripjaggerdojo.blogspot.com/2010/08/witch-who-came-from-sea.html

Don't know about the artist, but I must say it's a candidate for most misleading movie poster of all time!

Even if it was "borrowed," the use of Millie Perkins' face was of importance, and while many feel it has nothing to do with the film, it actually does. If you watch the scene where she's looking at Botticelli's painting The Birth Of Venus, the dialogue there explains everything and thus the title of the film, the cover art relates to it all.