At a guess based on the style, mid 1980s quartz model using the 1430 quartz movement (which is apparently a rebadged ETA 255.111). This is good and bad. If it is currently running you are all set, if it is not, it could have battery inside that has dumped acid all over the movement meaning it is scrap and needs replacing. Value wise, if running a few hundred maybe.
EDIT: It looks a lot like, but not identical to the Mariner III model. Perhaps it is a later version of that.