Welcome to Ausmini! Depends on what the problem is.
I would take off the slave cylinder and dismantle it and put in a kit. The arm might be rusted or ceased but most likely can be cleaned up. Here is a new item:
http://minikingdomonline.com.au/product ... -cylinder/While it's out you'll want to do put in a repair kit on the slave cylinder:
http://minikingdomonline.com.au/product ... -cylinder/If all else fails here is a brand new slave cylinder (Note you'll still need to buy the pushrod as I don't think they come with one)
http://minikingdomonline.com.au/product ... -cylinder/While you're at it, the hose to the slave cylinder might also be toast
http://minikingdomonline.com.au/product ... -cylinder/You'll also want a new washer between the hose and the connection at the firewall
http://minikingdomonline.com.au/product ... utch-hose/Obviously you'll want to drain the whole system and get rid of 20yr old fluid and bleed the whole system again after refitting. Some other bits and pieces worth checking while you're down there is the state of the master cylinder, the clevis pin connecting the pedal to the master cylinder, the clutch arm itself (and the condition of the ball on the end of it) and the clevis pins that hold the clutch arm in (two of them 1 at the top holding in the above salve pushrod, bigger one at the bottom holding the arm onto the clutch housing). Also need new split pins for said clevis pins. All those clevis pins cost nearly nothing to replace but make a HUGE difference to clutch travel and activation.
PS. suggest you put your location into your profile, that way if there are members near you could lend you a hand. If you're near me I'm more than happy to help!