pretty sure you can get frame sliders for a zx11...You could even try just buying the plastic slider for any model with a fairing and then just getting 2 longer engine mount bolts...it would be the same thing.
Some mid 90s and 80s bikes it's basically impossible to find frame sliders for unless you DIY or mod ones for newer bikes. I had a zx1000r and it was a PITA to find anything other than exhausts for lol.
Good luck, I love kawasakis
