I think the site is bugged. Says in stock, allows you to select and order in store, but sends you an email saying out of stock and no reservation number.
Does that if you try to order more than the amount listed as 'available' to order, which in my case was 1 (and appeared to be 1 for every local store that allowed it too), bet if you retry and just order 1 the confirmation will work, did for me anyway, same for the grip.