in the absence of a shop made of bricks, The Big Green Bookshop ebay site is up and running. And look at these precious exclusive things that you can buy!!
WOW, i hear you say. But wait, that's not all. You'll get a signed official TBGB certificate of authentication with your badge, so in years to come, when The Big Green Bookshop is bigger than Wall-mart (but still lovely of course), you'll be able to sell it on ebay again for a fortune!
alternatively you could wear it.