Vintage Janzen blazer jacket

Vintage canary yellow Janzen blazer jacket with white piping. Single button. Faux front pockets. Textured fabric, no content label. Likely polyester or synthetic. Label says 10, but measurements are much smaller. Chest 17", waist 15", shoulders 15", length 28". Based on measurements, listing as small. One small mark on back, see photo. Upper lining only. Bright lemon yellow.