In this schematic the "Nut, Flange, 8mm" is used most often.
The most reasonably priced component used on the Cb750c 750 Custom 1981 (b) Usa Stand is the Nut,hex 10mm.
Some items from this specific schematic: Spring,d Stand, Bolt,flange,6x28, Cover,stand Spg., Pin Cotter 2.5mm.