Rebuilding an engine completely may include new pistons, crank-shaft/con-rod (little and big-end) bearings, main bearings and a host of other small parts that are better replaced than reused; piston-pin, circlips, con-rod bolts (which should always be replaced to allow the correct torque to be applied when tightening).
In short, this is a task for skilled mechanics; but one thing for sure, the more components you can afford to replace, the easier the task becomes, and with better results.
Of course, you may be lucky, and only need new piston rings, either way you may wish to consider the components listed below:
920011793
130310770
132340591
132510037II
920281422
921390782
920281423
920281424
921390783
921390784
921390786
921390787
921390788
921390790
921390791
921390792
132BB0610
110050653
110050675
110610790
130010742
130020710
130080047
920330732
Add as many new parts to the same shopping cart as you wish, new woodruff key 92038001 washers 92022304 & dowel pins 920431264 for example, and still only pay the same single fixed price shipping cost. Important! Please be aware that this component will have other applications within the Kawasaki model range, so check the part-numbers you order are correct for your model and application. Pro-workshop gasket sealant 08CRAHLG120G - easy to apply with pleasing results.