A:AnswerIt has to be a prefect fit in order for the case to work. If it's not a prefect fit the phone could create a pocket, you may not be able to see, and case water to leak in.
A:AnswerFor this you would have to call best buy corp number or visit your local store. most of them can special order it for you right to the store or your home. If they cant do it in store or through the best buy corp number then it is up to the manufacturer when they are going to send out more of that product.
A:AnswerI've never had a problem exchanging anything at Best Buy. Provided the product is in its original packaging I don't see an issue with an even exchange. I've done this with and without a receipt. However if the item is out of package and shows signs of use you may encounter an issue. I suggest taking the item to the store to check and see what your options are.