For what it's worth, I made a guess but Accardo, Black Joe, and Caesar DiVarco were the only three I know I got right as Joe replied to my e-mail saying I only got three. I also guessed Prio (guy with cigar), Solano (guy sitting on bench), Cerone (as the bald guy not facing the camera), and (for lack of any better guess) DiBella, even though none of the remaining guys resemble him.

From what I can gather, the remaining guys don't resemble any Outfit bosses or capos that I can think of (based on our limited existing photo evidence) so whoever guesses this right had to have been tight with some of these other players at the time.