Vintage 1970s short sleeve womens button down pocketed shirt unbranded RETRO

Black with retro orange flower design. No tag so unsure of brand, but very well made. Buttons are white with gold rim and one button is held on with a safety pin. Small opening along hem under right arm. Small Run in the fabric on the back. See pictures! Appears to fit like a medium…16 inches armpit to armpit -and 21 inches down the front. A very unique piece.