Shopping verifying event heads

Generally, receipt of the original order the head was an event of is the best you're going to get for an event head. I do wish Fairyland offered COAs for all parts, but alas. Mostly have to rely on trust.

Another possibility for verifying authenticity is if this is a more recent order and they got the doll through Denver Doll, since they now send out cards verifying that a legit doll was purchased through them.

 

I believe all Fairyland Event heads have their event name stamped/etched inside the head, so you can ask for a photo of it.

 

Do you know how recent it was? To my knowledge they didn't start doing the card until this last year or so. To my understanding, Denver Doll will just send a certificate along with the doll.

 

I agree, a receipt is a pretty good indicator of authenticity. Sure, anything can be faked, but it seems unlikely in this case.

Other than that, just a good general knowledge about the item you are purchasing is the best defense. Things like making sure the production year matches when the head was released, the color being one that was actually sold by the company at the time and making sure that any markings look right. The more you know about what the item is supposed to be and look like, the more likely you are to be able to spot any discrepancy.
The same goes for the seller, of course. If they are well known in the hobby, have a good reputation, is known to own legitimate dolls etc. they are not very likely to try to pass off a recast as the real thing.
Vigilance is good, paranoia isn't.