The component with the lowest price in the TRANSMISSION schematic is the Screw.
Parts such as the Transmission: Gear,sixth Driven, Seal,oil(25x40x7), Gear,second Drive, Circlip are included in the Rs175 1981 (x) Usa (e03) Transmission parts fiche.
The Transmission assembly is constructed from several parts from which the Shaft Assembly,counter is the most expensive.