12 string acoustic - identify year made?

[Iantpdx]

Hello. I have a 12 string acoustic Framus that was my father's (and my first guitar!) . He is turning 75 in a few weeks and I'm giving it a complete tune up so he can display it. He doesn't remember much about it, so hoping to get some info to share with him. I've attached pictures of the label inside the guitar and the number on the back of the headstock. The headstock number doesn't seem to follow the normal formatting, making it hard to identify the year it was made.

Any help would be greatly appreciated! Thanks!

Model: S/299 (hard to read)
Serial: 1870
Tested by: (blank)

Headstock number: 547-84-9601

[disposable user]

I have a theory. If you could show the front of the guitar and, ideally the neck joint as well, I could possibly date it within a precision of a few months.

best regards, Dispo

[Iantpdx]

Hi. Here are the pictures. Thank you!