Check out any of the seventeen Cam Chain / Tensioner components enlisted.
With a quantity of three pieces, the Bolt,flange,6x16 is the most used part in the CAM CHAIN / TENSIONER diagram.
Some items from this specific schematic: Bolt,hex Kno 7x17, Nut,hex 20mm, Bolt,flange,6x16, Nut,lock 20mm.