For men, I've always thought of this picture as a good example (besides being a very beautifull photograph). It is taken by George Rodger and the subject is the winner of a traditional wrestling match. Nuba are not hunter-gatherers though...
I can't think of a female example (although the words scarlett and johanssen come to mind ;-)
[UPDATE] I found a few pictures for female healthy bodies, from Leni Riefenstahl (famous but controversial German filmmaker and photographer). Again this is not from a hunter-gatherer society. And these girls are relatively young.
And I also like the idea touched in a previous answer: eat like a H-G and move like a H-G and you will know what a healthy body looks like. For a man, I think you will end up something like the fantastic Erwan LeCorre (from MovNat). Ofcourse, the would be no evolution without variation, so some will be bulkier, some will be more slender.
