Hermle gold and glass dome pendulum clock

Hi all. This clock was a 50th anniversary gift to my grandparents in 1996.
On the gold engraved metal face the maker's signature is "Hermle" near the 12 o'clock position. At the bottom of the face "made in Germany" is printed. On the back of the clock it is embossed in relief "made in W. Germany."
It has a clear glass dome as pictured and a cut glass base, with gold paint facets around the base. The exterior housing of the battery area seems to be made of gold plastic but the pillar supports and four golden balls of the pendulum seem to be a gold metal finish.
It keeps perfect time and is just missing the cover for the AA battery.
I've tried to find similar ones online, just to get an idea of how old it might be.
Anyone who can shed some light, that would be awesome!
Thank you