I believe not. Seiko started dominating the COSC trials in the late 60's and quickly the contest was stopped. in 1972 COSC started certifying watches. The contest resumed about a decade or so ago with the requirement that all parts must be of European origin, I believe that this does not apply to COSC certs. This being said, "officially certified chronometer" or even having chronometer on the dial is defined by ISO 3159 first codified in 1976, and the current revision is dated 2009 and was recertifed in 2015 with no changes and is to be reviewed in 2020. So date of the watch is needed on the piece in question. That being said Seiko in 1976 could have had an inhouse test for ISO3159 and legally labeled the watch that way. Currently afiak there is a German Body that can certify a watch as a Chronometer and the watch would not go through COSC.