I recently came across several photographs from the 1950s-1960s of Danish architect, Arne Jacobsen, using a leadholder. Please refer to the attached images.
If you look closely at the third image you can make out the blurred branding/imprint on the barrel.
Does anyone happen to recognize this specific model?
I think as well it is a piece by Caran d’Ache, most likely some Fixpencil for 2.00mm with plastic pushbutton (if it is metal, it surely looks like a dark colour, maybe violet or red).
Fixpencil 2, II or 22 (with smooth body) is my easiest guess. Great choice, by the way.