The Fiend of Dope Island (1960)

A woman jumps up out of the ocean water briefly showing her bare breasts. It happens so fast you can't see them unless you slow or freeze the footage.

A woman is sunbathing topless face down on the ground when a man sneaks up on her. She's startled and jumps up revealing side breast before she covers herself with a beach towel.

A topless woman is sleeping in bed facedown in a hut when she's startled by a noise and rises up slightly. Her breasts are slightly visible but in shadow.