Relance red pleated blouse

Purchased from a Montreal vintage boutique a few years ago, this is a red button up dress shirt or blouse with a geometric print. Not sure of the fabric but the tag says "Reliance" and appears to have been made in Canada. The shirt features some amazing pleating on the front and the sleeves. It's in great shape except for a small hole near the collar on the back right side (see photos)---barely noticeable. There's no discernible size label but I'd call this a large (size 10 or 12). Measurements flat): Pit to pit: 20.5” Length: 23” Sleeve length: 21”