Thanks a lot for both posts ! I know well about Kienzle and have bought from them in the past. I will write them and let you know.
I think, if I do not find the part now, the priority is to fix the enlarger head myself. Not so difficult. Then I will probably take time to find this part at a reasonable price.
You're welcome! I don't know how I found out about Kienzle, they are not that well known where I live, but their range of enlargers appears to be quite impressive. I would love to see some of their products in person. I would love to be able to get one of their small color or VC heads to put onto my Valoy II. I'll bet they would have no problem supplying an adapter that would fit the new head to my enlarger perfectly.