The Screw,cross,4x6 is the cheapest item from this partsfiche.
This schematic depicts all components used in the Cb750c 750 Custom 1981 (b) Usa Air Cleaner partslist.
Some items from this specific schematic: Case,air Cleaner, Duct,air/c In, Elmt,air Cleaner, Screw,pan,5x25.