The Savage She-Hulk #6 comic book from Marvel Comics Group
Now this would be a battle.  The Incredible Hulk is too much for Iron Man, but the She-Hulk is not as strong.  I would still go with She-Hulk on this one, but it would be a good battle.

       

This is a scan of an old comic book. This item is not for sale. But you can find it on ebay.
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