The above picture is a scan of the tag of a NWT (new with tag) deadstock Ben Zuckerman dress and coat. The outfit dates from about 1958.
The average wage for Americans in 1958 was $4650, so this outfit, orginally priced at $535 represented about 12% of the average wage earner's yearly income. Ben Zuckerman clothing would have been out of the reach of most Americans.
Jacqueline Kennedy, as first lady, was a customer of Ben Zuckerman. Hamish Bowles, in a Vogue article states that:
Despite the thoroughly American feeling of her clothes, at times she (JK) included copies of Givenchy originals in her line. The Romanian-born Zuckerman was a fashion-industry stalwart working with his designer, Henry Shacter, to produce “the only clothes made in America that look as though Dior or Balenciaga made them.” It was Zuckerman’s line-for-line copy of a Pierre Cardin coat in purple wool that Jacqueline Kennedy had at first decided to wear for the Inauguration Day ceremonies (she wore it instead to tour the White House with Mamie Eisenhower).