Well, the Raven that
@polywog shared IS a free model on Renderosity. Commercial use is OK too!
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Not sure how pose-able it is... I'm downloading it for myself seeing it's free, but I"m guessing it's just a static prop... will report back if I find out otherwise.
This one is pose-able, but it's not free:
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Two other options (also not free):
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(cartoon-ey)
Anyways, the point here is that, if you can replicate the pose or otherwise come up with a compelling pose of your own, then there won't be any question r.e. the usage rights 'cuz you set up the render for your logo, etc. yourself!