Hi, I've got a Kili Racer
Think your find the steerer to be 1 and 1/8th, unlikely you'll find some original rigid forks, you could look for retro suspension on ebay but I think your better off getting new if you have to, or if your ok with rigid get some project II's?
I think your asking if you could put some new sus forks with an aheadset on, yes but try to get no more than 80mm travel - think that's the shortest you can get now anyway? - but you will also need to get a new headset, stem, v-brakes, v-brake lever (no cable stop on the fork brace for canti's) - you could still use canti's with rigid forks cos you'd just need a cable stop thing?
Good solid frame, that'll still be out on the trails long after all those Fat's and old Roberts have rusted away
Then one day you find, 10 years have got behind you ....