In the 1972 documentaries, Richard refers to Vincent Price playing Anwar. And he was still called Anwar at that point. By 1972, Anwar had already been redesigned to look more like Price ... he would get further redesigns later, his design finally being nailed down in the "cards" shot.
I'm not sure about Art Babbit's work on the character, which seems out of place in any era. That could just be due to Babbit's style rather than anything else.
The 1974 date is a possibility.