Good luck. As a stick-in-the-mud advertising executive in the Mad Men sixties, Darren usually wore a business suit, slept in pajamas, and was never shown in the shower or at the beach. Dick was suffering from a debilitating back injury that prohibited most stunts and action scenes; finally the writers had to find reasons to keep Darren in bed for entire episodes.
But you can find everything on youtube. A compilation clip called Dick York: the Sexiest Man Alive seems to be displaying clips from Dick's very early work, playing high schoolers in "educational films" such as "How Popular Are You?" (1951). They were used in classrooms for promoting conformity and compulsory heterosexuality.
But the compiler finds some gay-subtext images. Dick and another boy check out each other's equipment in the shower (top photo), and he demonstrates that he is popular by walking off arm in arm with the school hunk.
Democratic Underground. Not a bad physique. Too bad Darren didn't get zapped out of his clothes from time to time.