Some items from this specific schematic: Oilseal,15x25.5x7, Valve Comp.,reed, Insulator, Carbu., Gasket, In. Pipe.
On this parts fiche the Screw Cross 6x45 is the most specified component.
The component with the lowest price in the E-5 CRANKCASE - INLET PIPE schematic is the Bolt,stud 6x32.