Waterman number 8 - Maybe ?

[MarcoA64]

My great-grandfather was given this pen buy one of his patients after a visit, as he didn't have a pen that day give the urgency of the summons, to write a prescription. The year was 1939, Minitry of Interior, Rome.

I admit that I have tried using it but it is a bit too wet.
I've read on Waterman's pens on Lambrou's book but this pen is a complete mistery to me.
As is the colour pattern which seems one of the early years one.
For instance when was the 'clip clap' inscription removed / added to the clip ? Mine has Waterman's

one.JPG
two.JPG
eleven.JPG
three.JPG
eleven.JPG
ten.JPG

Ideas ?
Thank you
Marco