1980’s Adolph Schuman For Lilli Ann nylon fit and flare dress in gray & pink. there are a couple flaws--small red dash above breast (not visible if the collar is unbuttoned a bit. Also light deodorant stains under arm pits. I'd suggest wearing with a cardi if you're worried someone might notice.

14 inch elastic waist can stretch to 17 inches

19 inches pit to pit

I'd say this is a modern day size 6

This item is sold from an excellent, highly rated vintage boutique in New Haven, CT.