I recommend that you buy 3 or 4 on Ebay. Sellers sell thes in bulk on ebay, just look around. Most part numbers are the same, but you generally want a higher letter on the end (for your part number anyway). For instance, the part number on my '99 remote is 56036859AC. XJ's will support up to four remotes. It doesn't really take any additional time to program the extra three. Also, call your various dealers. Some will charge a flat rate, some will do all of them for free, it really depends on the place. If you are programming a second or third remote, it is wise to have all remotes present.