The Nipple-spoke,aluminiu is the lowest priced item on this Tires schematic.
A sample from the products for the Tires include: Wheel,rr,2.15x19,al N, Nipple-spoke, Tube-tire,mc90/90-21(, Wheel,fr,1.60x21,al N.
The most expensive part in this assembly is the Wheel,fr,1.60x21,al N.