Vintage PF Knits Parnes Feinstein‎ Union ILGWU Made in the USA dress

Vintage PF Knits Parnes Feinstein Union ILGWU Made in the USA dress. based on Union label I am dating this dress in the 1960s-1970s. metal back zipper. there is one tiny black mark on the dress very minor. all beads seem to be intact. no size see measurements- best guess would be a medium fit. no fabric content but feels acrylic or poly. . Bust is approx 19inches across