FYI: Bluetooth will be available for software only StreetDeck and the bluetooth dongle should work on any XP based PC. The cost to add basic bluetooth hardware to the Infill or to a custom PC should be the same.
I don't have anything to do with the MP3Car store so I can't answer your real question. Whether its possible is more of a question of is it practical to do with the ecommerce system, then a financial / licensing one. ZipLock has been notified of your request though.