Parts such as the Left Cylinder Head: Guide,ex Valve, Band,in.manifold, Plug,spark (nd), Plug,spark (ngk) are included in the Cx500t Turbo 1982 (c) England Left Cylinder Head parts fiche.
In this schematic the "Valve,guide" is used most often.
The Screw,cross 5x8 is the cheapest item from this partsfiche.