This turned out awesome. Glad it did indeed turn out to be a newly fabricated sculpt. I'll most likely be picking this figure up and posing him with the regular hair piece without the hat, holding the hover board in one hand and the Almanac in the other.
At first, I thought the EX accessory was Biff's revolver, which sort of perplexed me because as others mentioned, he never once even remotely touched Biff's revolver. After looking at it more though, I think it's supposed to be the gun he used in the Wild Gunman video game in the Cafe 80's.
I also see HT was still unable to obtain the Nike license.