The lowest price component in this Fuel Tank parts-list fiche is the Screw,pan 4x8.
The Bolt,socket,4x6 is the most widely applied product in the CB1000F 1993 (P) SWITZERLAND / KPH FUEL TANK ( four times ).
Some items from this specific schematic: Washer Wave 17.5, Cap Comp.,fuel Fi, Plate,fuel Cock L, O-ring.