Some of our stuff sells out faster than tickets for the Gorillaz tour. There are a couple ways to get what you're after though.
First, our email re-stock notification located right on the product page. (see picture below) It'll be associated with the size you need.
If there's no restock email option, there's a chance that baby is gone for good. However, all is not lost. You can sign up for our email newsletter (at the bottom of shinesty.com) as that's where we'll let folks know when we restock hot items or launch cool new gear.