OK, so what you have is the Specialized Future Shock fork, and it is probably an early- to mid-90s model. This fork is essentially a Rock Shox Mag 21 with slightly different lowers.

So if you want to look for information on working on this fork, search for Rock Shox Mag 21.

I would ask in places like the “Classic and Vntage” forum here on Bike Forums, and “Vintage, Retro, Classic” forum over at mtbr.com.

i had a Future Shock back in the late 90s. It was my first suspension fork. It was already well used when I got it in 1998. They were pretty good forks for the early 90s..

Good luck. I will be interested to know what you find.