After a lot of help of the members of the omega forums and by looking at a watchbooksonly page on Instagram it turns out that this watch is a bit of a rare find so I’m reaching out to you guys to better understand the value before I can try to find it a new home.
Appears to be the "Aviator Sea Diver" I wouldn't call them that rare. From the web. I can't seem to find the standard pick of the Aviator Sea Diver on this forum
There is a whole book about the various iterations of these from the MoonwatchOnly authors. The most I've seen them post one any variation for sale is for ~$5500 USD, but that is with a Watchfinder ID write-up/ book. So real world would likely be a bit less.
Need better pics but a good example will get you around 2000EUR, a bit more for an outstanding example and a bit less for a not so good example!
There is not a CROTON or NIVADA GRENCHEN logo on the dial BUT a retailer's name (Rudolf's) so Iam not sure if its price is as high as the prices others has mentioned above. one of those sold here: https://omegaforums.net/threads/1960s-croton-nivada-grenchen-chronograph-aviator-sea-diver.40033/
Hi there - nice looking watch, the retailer's name on the dial doesn't really add any value (like Tiffanys) but it rarely detracts from it. these go for 1500 to 2500 EUR typically, depending on movement and condition. This is a Venus 210 movement I believe. Those with the Valjoux 23 and 92 column wheel movements tend to reach higher money, alongside panda dialed variants. https://www.invenitetfecit.com/modeles/chronographe-nivada-chronomaster_en.html