What he's saying, as far as I can tell, is that the person on eBay has recast (by the looks of it) the Sideshow Iron Man bust and is selling the helmets from that mould. At least that's what it sounds like.
As much as I hate it being done (I'm one of the more anti-recasting people you'll find), I know a lot of people don't see it as being bad and honestly don't care. So chances are you wont get as much support as if it were someone recasting something that a member here made, not saying that is going to be the case here, because it might not be, but just be aware of that.
Sad thing is that was one of the first comments I heard on another board when they announced that bust, someone talking about dropping it in some silicone...
You can try reporting it and see if they do anything but don't be prick and abuse the guy or anything.