Vintage bathing suit dress in yellow poppies

The most insane vintage one piece bathing suit with a built in dress (or skirt?) in a yellow poppy and blue pattern that feels like it’s from the sixties (or early 70’s?) but I don’t know for sure. Purchased from a vintage store in San Francisco but never wore it myself (had bought it for a festival but never got around to wearing it). This piece is amazing, held on to it forever but it’s just not getting wears and deserves to. Sizing says 11 but have no idea what that means, I would say it fits an XS or Small (I’m 5’2 100 lbs 32b and modeling in the pics) but I would say it could fit slightly larger especially if you cut out the cups which are slightly wonky from being vintage — see pics). Torn on selling hence the price 🌼