Vintage 60s Black Mod Dress

This is a super vintage mod dress from the 1960s. It has a union made tag on the inside (IGLWU) and a metal zipper that goes down the back of the dress, probably dating it back to 1963 or earlier. Tag says size 12, but sizing has changed over the years. Please check the measurements to see if it fits you. Bust 18" Waist 17" Bottom Width 22" Length from top of collar to bottom hem 31" There is some light staining on the collar and one of the sleeves. Please see photos. Thanks for looking!