Character Slot Voucher?

So I decided I'd break down and buy another character slot to try out the Trickster, but now I can't find the item to do so in the shop o.O

Unless I'm totally blind, but I've checked every tab of the shop. It was there before, so why wouldn't it always be available? If anyone knows why it isn't there anymore...or tell me I'm blind and direct me to the right section lol!, that be great.

Thanks.