The lowest price component in this Oil Pump parts-list fiche is the Pin.
With all the components that make up the GSX1100F 1989 (K) (E01 E02 E04 E15 16 17 18 21 22 24 25 34 39 53 OIL PUMP assembly. The O Ring(d:3.7,id:21.7) is the most frequently specified with four applications.
The seventeen Gsx1100f 1989 (k) (e01 E02 E04 E15 16 17 18 21 22 24 25 34 39 53 Oil Pump component parts are all listed in this schematic.