As long as it wasn't bought via cash, they should be able to pull it up via credit card #. They've pulled receipts of mine back to early 2002 via credit card. I think they might be able to do it via check as well, though I'm not sure about that.
If it was cash, the best they probably would do would be store credit on the lowest sale price of the game or the current price of the game, depending if their system does any type of legacy price checking like that.
Otherwise, they might just tell you to get lost. Not sure with BB these days.