Sorry, Nate. I didn't realize that the shock was so "special". Cannondale make some interesting design choices on your bike. It does sound like a new bike is your best bet. As Brent said, the bike blowout sales start soon and there are a lot of new, exciting trail bike models. Good luck in finding an appropriate replacement bike.
My upgrade was around $600, just about what the bike is worth these days. I viewed it more as an opportunity to learn a lot about bike maintenance. The upgrade does fix the two big issues I had, those being a 3x drive train and the lack of a dropper post.