The owner of Durst Pro USA has indeed passed away.
The website is still up but the phone line and e-mails are not being answered. It's too bad; it was a good resource for owners of Durst enlargers like myself. Over the years he machined needed mixing boxes, lens boards and other items for my Durst enlargers - they were as precise as the original.
I am pretty sure he did not work by himself - hopefully, the estate will be sorted out.
It's not about the look, it's all about the special mechanical connection of (whatever) knob.
I must confess, on the photo it is unfortunately not to be recognized well...
...and i'd rather sell the head including original knobs... ;-)