Kaleidoskop dobré pohody was a show on Czechoslovakian TV. In one episode from the year 1978 I saw two young women in the front row of the audience, maybe only friends, maybe sisters. The eyecatching aspect were coordinated outfits with white skirts and blue jean vests, only difference were the blouses below the vests.
British actress Jane Birkin appeared in a cowgirl / sheriff outfit in the French movie I'M LOOSING MY TEMPER from 1974, including a blue jean vest. Found in the WWW, displayed not chronological.
American actress Marilu Henner was one of the main actresses in the New York based TV-series TAXI from 1978. In the second episode of the first season, One-Punch Banta, Marilu wears a blue jean vest. I'm sorry, but at the moment the episode seems only to be available in a very low resoluted version, so the vidcaps are not really satisfying.
