Don Hawksley was a popular model in the late 1950's and 1960's for obvious reasons.
I have come across many images of him in the various beefcake magazines from that time. My favorite of these is the one in which he's wearing only a tee shirt.
This is Bob Delmonteque, the most financially successful of all the vintage beefcake models. While others like Steeve Reeves, Richard Dubois and Johnny Weissmuller were certainly much more famous, only Delmonteque went from successful nude model to photographing nude models to training Hollywood stars and even astronauts for NASA to owning a nationwide chain of gyms.
Here are two photographs of Kip Behar by Vulcan Studio. I especially like the intimacy of these images - it's almost like Kip is lounging around his house in a posing strap.
These photographs feature Bob McCune, another famous beefcake model from the 1950's. He is one of my favorite bodybuilders; he is spectacularly massive.
He is wrestling Herb Lamm in one photograph. I do not know who took these photographs.
I do not know who the photographer was, but the lighting and the classical theme of its jailed, nearly nude model attempting to break his bonds make me think the photograph was taken in the early to mid-1950's by Bob Mizer of the Athletic Model Guild.