They sell them on fleabay, then you just have to get them programmed. Only issue i see you running into, is if the key has a chip, im not sure if the switchblade-fob will have the chip to be programmed.
The actual fob is easy to program yourself, and most come with instructions when you buy them.
They sell flip keys on eBay. Quality is marginal. A former member here used a Rogue key which is not a flip key, but has the fob and key as one. If you don't have UpRev you will still have to have it programmed or switch your chip over to this one. There's a write up somewhere on here
I got a set of these off e-bay back in May. Still loving them and the quality is very good. Mine have the transponder chips which my local locksmith programmed and I programmed the remote with instructions found on this site. Just be sure the fcc# on the new remotes match your current ones.