Pretty good store if you are visiting the dc area and use the metro as you can buy a shirt and more depending if they have it in stock I did buy a nice shirt but it’s located in the ticket booth so it may take a while.
Not really a store, just a metro ticket booth that happens to carry a few of the items you can buy at their online shop. And it was out of most of them!
Difficult to find. Enter via 12th/F apparently.
Friendly staff, good selection of merch.