To discover exactly which parts you require use the on-line schematic exploded diagram - it will even give you some idea of where and how to fit those new parts.
This parts-list page (CRANKCASE) contains the most products with fifty-five listed parts.
With these XC125 2004 5ML1 SWITZERLAND 1C5ML-300F1 partsfiches you have access to seven hundred seventy-seven spares.