Help identifying Lewis Leather jacket

[Esinem]

I wonder if anyone can help me identify this Lewis Leathers jacket? My internet searches haven't nailed it down. Is it a Monza variant? The collar style and the single waist adjusters don't seem right for that though?.

I have had it for over 50 years. The main zips are all YKK but unsure if the pocket zips are. No labels inside as the lining fell apart and was replaced with Thai silk.

Thanks.

 

[Tom71]

Have you reached out to LL themselves?

The zippers are unlike anything I’ve seen from them so far. The other details seem off as well (sleeve zips on the inside, shape much less boxy and longer than the variants I’ve seen.)
If you had it since the early seventies, it may of course be something not produced in large numbers and long since discontinued. I trust, the good people around Derek have some kind of archive.