If it is just the bushings, it is an easy and cheap fix, about $10 and an hours work.
Where can I find the bushings?
Another thing, there is a small piece in the hinge assembly which looks like a flat piece of metal with indentions. These little indentions ride on the protruding downward hinge pin, and position the door at the several stop points as it is being opened. The force from the spring and /or repeated openings and closings caused the little flat piece to break off the bottom of the hinge pin. The doors still open and close fine, but if I am parked on a hill they will not open and stay open at all.
I asume the only fix is to replace that pin, which would be fine to do if I were putting bushings in.
The pins and bushings are avialable in the "help" section at any box parts store (autozone, etc). I'm not sure on the hold open portion, that may not be as easy to fix as that part is part of the hinge itself if I recall correctly.
Here is a pretty good link on the process to replace the bushings. I did most of mine by using various sockets and C clamps to press parts in and out rather than using prybars, hammers, punches, etc, but whatever works best for your situation.