GPZ 900r Starter clutch

Pay to spend the extra and buy a whole newy rather than put a kit through it

I agree - it costs a few bob more but the old starter clutch housing will have internal wear as well - if you just replace the springs and pins, these will wear out pretty quickly.

Best bet is to find a new ZZR1100 starter. This should last for years........

Any model zzr1100 starter clutch?

Yes - any model. Kawasaki tend not to change things like this from one year to the next, unlike Honda. Being the smallest bike manufacturer means that economies of scale are more important - so they tend to keep using parts that were tooled up by the same machines. That motor - the 900R/1000RX/ZX10/ZZR1100/ZZR1200/ZRX1100/ZRX1200 - was built from 1984 through to 2008, with what are only relatively minor upgrades to internals. But the *materials* they used improved a lot between 1984 and 2008 - so later-model parts are generally always better than early stuff.