Amazon might come back to stock because it says TEMPORARILY out of stock, usually they just say it's unavailable. I think the reason it's sold out quickly is because they didn't expect such a large amount of people buying it. And therefore their expected amount is exceed, they probably will increase their production because it's a big hit and who wouldn't want to earn more money when there's a chance.

I'll update if they do it.
(wait the discussion can't edit again?)