GAP, Gymboree, Children's Place and OLD NAVY usually do a good job of having cute, generic animal/character costumes for young children. Most stores I've talked to say they'll have their Halloween costumes out by Aug. 24th, so if you can just wait a couple of weeks, you may be able to find something that you could pass off as the White Rabbit! If not, try Ebay!Good luck! PS--If you can't find the rabbit costume, just go to the craft store, get a large white felt square and a black fabric marker and make a large felt "Playing card" that you could glue/sew to a shirt! He'll fit right in with your Alice theme!