This hat just slays me. It's a Seventies thing, emanating from San Francisco, made out of old Levis denim and known as a Camp Street hat. I had one from 1974 until it disintegrated from 20 years use.
Babs wearing one above, as pictured on the cover of her 1971 Barbra Joan Streisand LP. produced by Richard Perry and full of torch songs, I loved that album as well.