The twenty-four Nx125 Transcity 1989 (k) Italy Fr. Brake Master Cylinder component parts are all listed in this schematic.
On this parts fiche the Washer Oil Bolt is the most specified component.
The most reasonably priced component used on the Nx125 Transcity 1989 (k) Italy Fr. Brake Master Cylinder is the Screw Wash.,4x12.