On this parts fiche the Nut Conrod is the most specified component.
The most reasonably priced component used on the Vf750f Interceptor 1984 (e) E-13 Crankshaft Piston is the Pistonpinclip18mm.
The E-13 Crankshaft Piston assembly is constructed from several parts from which the Crankshaft Comp. is the most expensive.