Well, you could strike luck buying a "brand new" key via ebay, or you might end up with an unused 2nd key that has had a new blade fitted to, depends on your rush to sort this out and your liking to gamble. You can buy a new transponder chip I believe which would sort that "can't code it" issue, but getting to that point of failure might cost you a bit in time and money, then more money to request another coding, which should work if you buy a new chip from a reliable source.