[nonone]

Are you looking for the Air Screw? Part # VM20/214.
www.ebay.com/itm/172119470734

Or one of the variations there quite possibly could be others
http://www.aliexpress.com/store/product/Free-shipping-2PCS-fuel-ratio-adjusting-screw-Motorcycle-carburetor-Mikuni-the-carb-air-screw-For/1540211_32597630286.html

http://www.aliexpress.com/store/prod...633161488.html

At ~$10 your better off buying another carb like Bruce said. Extra parts always come in handy.

Here is some good info for VM's
http://www.vintagesnow.com/Carbureto...s/vmmanual.pdf