The lowest price component in this Rear Master Cylinder parts-list fiche is the Screw.
Parts such as the Rear Master Cylinder: Bracket Comp,reservoir Tank, Bolt,brake Fluid, Bolt, Piston/cup Set are included in the Vs1400glp 1998 (w) (e02 E04 E17 E22 E24 E34) Rear Master Cylinder parts fiche.
In this schematic the "Washer(10x15x1.5)" is used most often.