Originally Posted by eddie gunks
I don't know many serious collectors of photographica. The one I knew best was the late Charlie Barringer, co-author of the Zeiss-Ikon Compendium and one of the founders of Zeiss Historica.
I've seen many of his treasures, some of which were decidedly shabby. For example, an 80" Zoomar mirror lens with what looks like a bullet hole in the front mirror. For another example, a small pile of S-Planars and S-Ortho-Planars, all with badly scratched glass, dents, ...
I asked him why he settled for junk like that. He replied to the effect that they were plenty good enough for him and that because of condition their prices had been very right.
Also, there are still machine shops that will make flanges.