Since I never cared for those wooden artist's mannequins, I recently purchased a couple 1/6 scale posable male figures, that are apparently some fanboy/hobby thing. While they came with two sets of interchangeable hands and three penises (in varied stages of arousal) they did not include heads. Well I finally found and ordered heads from a company in Hong Kong.
I'm very surprised by the realistic detail. While having heads on the models wasn't absolutely necessary for my purposes, posing Mark Wahlberg with David Beckham is certainly more inspiring (or at least somewhat arousing!)