Hi all,
as i mentioned before i orered new sensors to replace the e3d cartridge type ones. A german shop i found stocks both PT100 and Type K sensors in cartridge configuration:
PT100 click
Type K click
the only drawback is that the Type K variant is only available as 4 mm diameter. They are not even expensive however and (to my experience) of much higher build quality than the e3d types. The lead length is variable and they feature ferrule ends matching the Duet Daughterboards perfectly (as opposed to the e3d types which have to be fitted). Last but not least they are specifically rated for 400 °C and 550 °C respectively. I am running the PT100 type right now and am finally able to print again.
Best regards, Niklas