The "L" shaped lever that attach's to the carburetor?
Part number is XXXXX(NNN) NNN-NNNNand will cost you $3.10. It is available and in stock.
You can not order it through this site, as we are just an advice board.
Contact your local Stihl dealer to order the part. To find your nearest dealer go to www.stihldealer.net Any dealer can order this part if they don't have it in stock