Do you just want it reserviced? Revalved? Did the nitro charge go flat? You need to have a servicing valve installed if you want any work done to it.

I do all my own work. Typically, the o-rings in the nitro cannister go hard and dont hold a good seal. You cant get the parts from Honda, but they are readily-available standard sizes.

If it isnt leaking any oil, the shaft seal should be OK. If it is, most any of the street suspension tuners can change it out. The CBR600 F3 (and a few other CBR's) shock uses all the same consumable parts, though the spring valving are different.
_________________
Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
MY BIKE PICS