I am trying to buy one more xfi pod but all I get is they are unavailable.

I want to buy one xfi pod, I got one pod for free after my wifi evaluation but I really need one more. Every time I try to buy one I get a temporarily unavailable message. Does anyone have an idea when they will be back in stock? Can I get one at the xfinity store? I thought the last time I was in the store they had them for sale.