If your machine has a broken Bobbin Winder, keep the original screw and washers, and replace it easily with this vintage original part. This is sold
Vintage sewing machine for reenactment: Singer 66 with hand crank –
The Singer Featherweight Shop
Bobbin Winder Disassemble and Reassemble Singer 66-1 Bobbin Winder
Bobbin Winder Complete Unit, Singer (Vintage Original)
spool pin cover - The Singer Featherweight Shop
Only 19.99 usd for Vintage Original Singer Bobbin Winder Assembly Fits Singer Model 66 Online at the Shop
Bobbin Winder Friction Wheel
Bobbin Winder, Complete Assembly (Original) for Singer 7000 Class Sewing Machines – Millard Sewing Center
Bobbin Winder, Singer (Vintage Original) – The Singer Featherweight Shop