Information wanted on Giulietti F94 C "Hagström"

[Svanis]

A few years ago I purchased this accordion from an accordion shop in Sweden. It's a Giulietti F94 C (C for Chromatic C-Griff) with a Hagström "Victory"/"Super Cromatic" style grill with a red felt sordina mute. The owner of the shop told me Giulietti produced accordions for Hagström on license. (Hagström was also a musical instrument shop in Sweden as well as internationally.) The grill is not a DIY job, it's custom made for this specific accordion model. Hagström did not make a 9+1 treble register accordion. I don't know if the microphone knobs and jack are original, it had no mics when I bought it.

My best guess is that the grill was an optional accessory you could have when purchasing the accordion from Hagström, and they started importing accordions from other makes when their own accordion production slowed down in the 50's to 70's while they transitioned to making electric guitars and amplifiers.
There's a Brazilian guy playing an F94C with this exact grill on Youtube but without the Hagström badge and a different Giulietti badge, so maybe it was available in more countries than Sweden.

My question is what year approximately this accordion was manufactured, and whether this accordion was made by Serenelli or Zero Sette? I have found many variants of this model "F94" with different styled grills, logos, and badges.

I know there are some very knowledgeable people on this forum. I can say that the accordion sounds very good with the mute, and there is no timbral differences between the rows of reeds unlike with the standard Giulietti grill as someone here has mentioned was the case due to the oval shaped design.

Everything inside the accordion is marked "200" from the reed blocks to the grill. Attached a picture of the reeds from when one fell out on me and I repaired it.