The one behind Dunkin Doughtnuts is Showcase, in Wheaton.Their is another on Bladensburg Road at 34th Street Next to Shoppers and another shop on Old Rhode Island Ave in Riverdale Park. Also Genesis Pets on Central ave. Tropical Lagoon in Silver Spring and their is another Shop behind teh Dunkin Doughnuts at Georgia and Reedie Dr at the far end of the strip.
For the OP, both Showcase and Tropical Lagoon often have GBRs.