Solid mystery. Hope someone can identify it, I haven't been able to find I direct match so far.
The face reminds me of an Elgin travel clock, they had a preponderance of dark insets and densely populated numerals. Plus, the Japanese clocks of the time were more design-adventurous.
The overall case design and pedestal are similar to an early
Westclox Big Ben.
The top button design looks more like a
Soviet-made Slava Sputnik Commemorative clock minus the orbital flourish. I was thinking a sputnik manufacturer might make sense from an establishing shot, trying to establish the period before the soundtrack is locked down. I wasn't alive yet so I don't know what export and import controls of '69 looked like, in terms of soviet-made alarm clocks making their way to U.S. headboards, if that would be apocryphal.
Keeping in that establishing-shot mental framework, a West German Kaiser brand clock might make sense as well and the top button design for the vintage Kaiser clocks is similar to whats pictured, though their designs seemed broadly more conservative.
Some of those listed here seemed pretty close in casing design though not in clock-face.
https://www.quintessentiallyfrench.com/product-page/french-vintage-alarm-clocks
Fascinating how many clocks from this era look like frowning robot faces from the back. I guess there are only so many mechanical movement designs.
This clock seems very similar:
Alarm Clock Fashion, 1970s For Sale at 1stDibs
Though the brand name "Fashion" isn't helping the search-fu and the date range of 70-79 is wrong.