Of all the components used in this assembly the Crankcase,lower is the most expensive.
A sample from the products for the Crankcase 82-83 include: Set Ring,72mm, Crankcase (upper), Bolt,u.b.s.,8x114, Bolt,flange,6x75.
The component with the lowest price in the CRANKCASE 82-83 schematic is the Bolt,hex 6x12.