Thanks to the CR list and listee DTShifter I have located a MAVIC rear derailleur stop. But I have just now closely examined the MAVIC labelled version of the a Simplex Retrofriction shifter I purchased off Ebay and realize it is missing the right side pivot screw. Again I would like to appeal to the list members for their assistance in finding this part. Happy New Year from Wichita, Kansas, Rodney Handsfield