The standard 8" adjuster cam is only available second-hand. These oversize cams are deigned for use with skimmed drums to return the normal range of adjustment. At the lowest adjustment setting they are 1/8" taller. To use with standard drums and new shoes you may need to slot the brake shoes to allow the drum to fit over.The actual snail cams don`t usually wear out, they are not meant to be sharp ! The retaining mask FBK111 is more likely to need replacing. If you cannot get the correct shoe to drum adjustment you will need to change the shoes or the drum or both.