k-jetronic help required

After looking at my fuel mixture ive found the fuel mixture screw missing

A = does anyone have a spare i can have please

B =where s the best place to buy a new mixture metering head from

Thanks in advance 

I don't,  sorry.  However deutche doktors might. They buy and keep loads of mk1 golfs for restoration. They also do lots of engine conversions, so have secondhand parts from the removed engines.

https://www.deutschedoktors.co.uk/contact/

mixture screw ?