I tried to unfreeze mine and it wasn't happening, so I had Ford make me another one for over $100. Alternatively, you could remove the cylinder and take it to a locksmith, leaving a copy of your key as well. They can get the barrel out and probably replace the tumblers too. When I was a prankster in high school, I took my school-issued combo lock to a locksmith and had him make a copy of the master key that would open every locker in the building. They can do amazing things, and even a teenager can afford it.
Toby