The most expensive part in this assembly is the Head Assy,cylinder.
Parts such as the Cylinder Head: Gasket(5.8x13x1.2) (nas), Head Assy,cylinder, Bolt, Plug,spark(ngk Cr9e) are included in the Xf650u 1997 (v) (e22) Cylinder Head parts fiche.
The component with the lowest price in the CYLINDER HEAD schematic is the Ring,snap.