Barbarella, 1960's, Science Fiction.
Starring Jane Fonda.
A 1960's classic, this Russ Meyer film stars Jane Fonda as a very sexual, space traveller.
In the opening scene Barbarella is floating around the spacecraft nude.
Hawaii, 1966.
Starring: Max von Sydow, Julie Andrews, and Richard Harris.
"This film includes many examples of bare breasted Polynesian women who slip through the National Geographic loophole.
Tarzan and His Mate, 1937.
Starring: Johnny Weismeuller as Tarzan, Maureen O'Sullivan (Mia Farrow's mother) as Jane. Tarzan and Jane enjoy a rather long swim with Jane being completely nude.
I know the Last Picture Show was filmed in 1971, but it shows young Cybil Shepord's boobies.