The most reasonably priced component used on the Ttr125 2003 5hpf Denmark 1b5hp-100e2 Rear Wheel is the Nut (89w).
Some items from this specific schematic: Puller, Chain 2, Nut (89w), Axle, Wheel, Brake Shoe Kit (nas).
On this parts fiche the Bolt, Stud is the most specified component.