Hi, Omega Forum! My father bought this Seamaster after he opened his practice sometime in the 70s. It was his first “real” watch. I had the mechanics serviced, and it could use a proper cleaning and polishing. Been looking through the threads for suggestions on replacing the band (it’s not original). Please pass along any pertinent threads! I’ve never really thought about its value - it’s a sentimental item that reminds me of my dad.
Welcome to the forum! Seamaster Cosmics are well-loved on this forum; just type "Cosmic" into the search page and you'll find some 400 posts on this model. Avoid anything other than a light polish by hand if you can, as machine polishing will smooth out those sharp case edges. If you've had the movement cleaned and serviced and the seals replaced, you're good to go for many years.