Hi Hacker,
There is a 6cm LTM lens for sale for US 895 here:
http://www.brooklyncam.com/inventory/leica.shtml, not mint though.
There is a black, non-coupled 85/2 LTM Sonnar for EUR 790 here:
https://www.leicashop.com/vintage/leica-lenses-for-leica-screw-c-1000_1010.html
Igorcamera had some post WWII aluminum RF-coupled copies for around US 600 or so.
I have never seen the original LTM/coupled chrome and brass one listed anywhere, the one that is shown on cameraquest.com.
The Quinon 50/2 is a Sonnar.
Also, please open the list to Ernostars. The 40/2.8 is an Ernostar. Then maybe you could add the 90/2.8 M-Hexanon and maybe the converted Contax G 90/2.8. And, BTW, the ZM 85/2 (even though called "Sonnar") is a double Gauss design.
I am wondering about the various Komura lenses (85mm and 105), and also about the longer Fujinon lenses.
Best,
Roland.