Research leads me to believe this Swiss made accutron watch is a model name is "Beau Brummel AX" based on the 1972 catalog provided on this site. In the 1974 ad it is referenced in stainless steel as only "213 01 03"
It is a 13 jewel 2313 movement marked as "N6"
Under the battery it is marked 9-6 in black ink
The case back is marked with the serial number 5-200315 as well as marked 7866-1.
It does reference the battery type to use as "accutron 218"