This CAM CHAIN - TENSIONER assembly utilises two Bolt,knock 7x12(s) - the highest specified component.
The most reasonably priced component used on the Cb250rs 1982 (c) European Direct Sale Cam Chain - Tensioner is the Washer Seal, 6mm.
Parts such as the Cam Chain - Tensioner: Bolt,special,6x28, Sprocket,cam, Collar,6x14.7, Bolt,special,6x24 are included in the Cb250rs 1982 (c) European Direct Sale Cam Chain - Tensioner parts fiche.