Can't remenber the number, but can 'see' the car. The model '404' keeps jumping into mind, but I'm probably wrong. At least i knew it was a Volvo, a Swedish car, from Sweden. (Of course, I was able to read the small text stamped on the seat belt mounting point which read 'Volvo, Sweden'.....got you searching now, haven't I?!!!)
The only thing I could find with a similarly fat B-pillar was the PV444 and that's heading in the chronological wrong direction, so I guess no seat belt there