Sefram is likely to be of French origin. Generally, the straighter the pick, the older the axe.
: Another reference here: A model H9551-1 made by Leonhard Kost produced in 1910 has a very similar head shape, though without the serrated pick, indicating that your axe, with serrated blade, is post that date. Serrations were a later innovation. Though both axes have similar pitting in the metal, indicating similar steel and source. Later axes contain more chrome and rare metals and thus more resistant to corrosion: NiCrMo steel.
You might try using a strong magnifying glass and check all over to find any corroded out engraver's mark.
(open 2 tabs and flick between) This axe is 245mm (9.7") wide, and maybe 42" long, though the info is ambiguous.
I'd like to see a different angle (turn shaft 90deg to lens so we can see the insertion front and back, as there is something odd there). And how wide it and how long is the shaft?
Other info: (STUBAI) axe. Where a STUBAI logo is enclosed by a diamond, it would be pre World War II. If the logo is enclosed by a mountain, it would be after WW II