On this parts fiche the O Ring,10mm is the most specified component.
The seventeen Kaf620-ref Mule4010 2014 Usa / Trans4x4 Gear Change Mechanism component parts are all listed in this schematic.
The Kaf620-ref Mule4010 2014 Usa / Trans4x4 Gear Change Mechanism consists of seventeen pieces with the Lever-comp,change,2wd being the most expensive.