I get frozen pitted sour cherries from the Russian market in Washington Square. I can't remember its name, but it's close to the Starbucks and Emack and Bolio's. I've never used fresh, but these frozen ones make a mighty tasty pie.
That does seem like a lot for shipping, but I have paid for shipping from Michigan. Maybe you can get a larger quantity with comparatively cheaper shipping because buying in large quantity, and split the order with a friend.