70s' style - a good example though?

Looks like ref 168.019. The photos suggest some wear on the bezel- but some of the dark sections may be due to light angle. The case is lightly refinished/rebrushed and edges are soft- which is common with 18k gold. I would say it is fair + example- I think it is overpriced by about 1000 pounds- if you are in a rush and love it and its serviced with documentation that helps- but I doubt you would come close to recouping this price if you wish to sell it down the line.

the 169.029 with the fluted bezel is more attractive IMO look at the C Case Constellation thread here to see examples
https://omegaforums.net/threads/the-c-cased-constellation-thread.72308/

edit: the OM on the dial indicates solid gold dial which adds some extra value

This may sound harsh, but I see it as a mediocre example of a less desirable reference (day-date C-case). I get that you see it as a fun and quirky 70s watch, but it's not something to spend serious money on, IMO. I don't know the asking price, but from the comments above, I'm sensing it's a big number. If you want a c-case, buy a gold-capped or SS example, so if you get tired of the dated look, you won't take such a huge loss on resale. Save the big money for something classic and desirable.

If you're looking for a larger gold vintage watch, take a look at IWC. Omega isn't the best brand if you're looking for larger dress watches; there are a few larger references, but they are rare.

Alternatively, there are some vintage re-issues that would be a good option for you, although they are probably more expensive.

I’d go further than saying the case has been lightly refinished, it’s been heavily refinished to the point where the facets ok the side of the case have been completely lost. Unless very cheap, ie around the value of the gold, I’d pass.