Found a couple of outfits making repros, reasonably priced.
http://www.kdirepros.com/Tachometer-Damper-p/237-83523-00-00.htm
http://pgmrubber.com/index.php?route=product/product&product_id=185
https://sumorubber.com/en/237-83523-00-yamaha-tachometerspeedometer-bracket-damper
They have other offerings that may be of interest...
http://www.kdirepros.com/Tachometer-Damper-p/237-83523-00-00.htm
http://pgmrubber.com/index.php?route=product/product&product_id=185
https://sumorubber.com/en/237-83523-00-yamaha-tachometerspeedometer-bracket-damper
They have other offerings that may be of interest...