Oh, wonderful, wonderful on all fronts. Great info there Axel and much better than my guess. I wondered where you had been and guessed you had been digging as I saw quite a lot of dust your way. I still would guess that FN was the Belgian source.
I still find it odd that it doesn't wear the wildmann with a club mark of quality. I would say the tubset was sourced but it does wear a touchmark of a "W" on the underside of the right tube just forward of the flats and a scrip "W" on the lower rib just ahead of the flats, both marks typical of Sauer mechanics.

Kind Regards,

Raimey
rse