You'll have to post some detailed photos of the watch, its sort of like asking what a Ford is worth, it can be $1 to $300,000
OK, Seamaster Day Date Calibre 1020 Circa 1970s, after service probably worth 300-400 but it will need servicing if it hasn't had it already.
It does look too nice to.be so old. I did pay 325$ us plus shipping for it. I wasn't sure what vintage seamaster go for. I've seen others similar posted on ebay for 900us and thought I got a deal .
a better strategy when not sure is to.....post pictures here and ask before buying...and BTW... relying solely on eBay listings for a price comparison is not a component of a better strategy