Do i need a new release fork?
 

My release fork loooks ok (except for the rust). Doi i need to replace it, or am I ok to reuse it?

Check for cracks. Douse it with an evaporative liquid like rubbing acohol to expose any cracks as it evaporates.

if it's the old style fork with the needle bearings in it, then you should invest in the update kit, which includes fork, shaft and bushings. the bearings wear notches into the shaft which causes a wierd feeling pedal. the tips of the fork which contact the t/o bearing also get notches worn into them.

I have the updated shaft and bushings which don't require drilling.

Might as well replace it--man I hate waiting for parts to arrive.