Can't help you with the choke parts, but I have some MC21 air screws.
Disclaimer: They are aftermarket. Never been used, and no idea just how good (or bad!) they are. I bought the kit for the rubber float bowl gaskets that were unavailable.
Drop me a PM if you're interested.
_________________
Andy.
NSR-WORLD.COM
Please keep all responses to Forum posts on the Forum so that others may benefit.
Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.
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