Parts such as the Thermostat: Cover,thermostat, Bolt,flange,sh,6x25, O-ring,30mm, Gasket,thermo Cas are included in the Cb600f3 Hornet 2009 (9) European Direct Sales / St Thermostat parts fiche.
In this schematic the "Bolt,flange,nshf," is used most often.
The component with the lowest price in the THERMOSTAT schematic is the Bolt,flange,sh,6x25.