Provenance research for a 1900-1930 Cartier fountain pen, any leads?

[omalleylaw]

My wife is an estate dealer and this recently-acquired fountain pen really really caught my eye.

After many hours of researching, I'm at a dead end.
Can you point me to research sources, sites, books, catalogs, etc?
Have any insights or thoughts?


Notes:
1920s at the latest (I conclude this because it is a Green box, so it predates Cartier's red box era).
Nothing is engraved on the engraving section (rectangular, see large photo.)
'Cartier' is written on the top of the cap
Box: Exterior- Green, floral garland design, almost-perfect condition, push button opener clasp works perfectly.
Box: Interior- white silk lining with gold lettering, perfect condition.

For the nib I did not find anything similar in online images.
Reading the etched type from tip to base-
(the typical heart shape opening)
"William" (fully written out, not initials like the Hicks nibs that I see online)
(a second, circular, opening. This is unlike any other Hicks nibs I see online. Grainy photo gives an idea)
"Hicks"
"New York"
"14k"

Misc:
My camera doesn't take clear extreme close ups, sorry.
Any leads much appreciated!
images:
IMG-1783small.jpgIMG-1782small.jpgIMG-1777small.jpgIMG-1783nib2.jpg

[Scrawler]

My word, that is gorgeous. That knurling is pretty distinctive. Could you get a good picture of the feed and filler. This would have been a gentleman's waistcoat pen, attached to a chain and fob of some sort. I don't know anything about Cartier but it's likely this was made for them.