They can be found elsewhere, but yes can be expensive. Evidently, someone made some reproductions, but think currently sold out. A few links that I found.
https://www.ebay.com/itm/KNEE-BAR-SI...p2047675.l2557
https://www.singeroriginalvintagepro...%20BAR-0000002
https://www.bonanza.com/listings/Kne...d-128/80675571
Accessory hardware inBentwood Case Lid
The bonanza one sold for less. The QB one I replied "My #191412 knee lever also has "99 mach 200 set" and "128 " 201 set""
I also read (on another board) that there were two people that had the opposite shaped knee levers for their machines, so exchanged them.
Janey - Neat people never make the exciting discoveries I do.
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