Vintage Brittany New York plaid/check equestrian riding jacket

Beautifully tailored riding jacket by Brittany New York custom styled riding apparel. Believe to be from the 1950's or 60's. Note there is damage to the fabric on the left sleeve below the elbow. No size or fabric content tag. It is most likely wool or wool blend. The woven fabric is beige, gray, black and gold with scattered specks of pink. 3 button closure. The bottom button was missing and I replaced with the one you see. Very close but not an exact match. Front flap pockets. Breast pocket. Listing as a size S. Shown on my size 2 mannequin. Please use measurements to insure a good fit. It measures 29 " Long. 18" across the top of the shoulders. 23 1/4" sleeves. Laying flat seam to seam it's 18" across under the arms, 15" at the waist. The left sleeve has 4 pretty small holes. I didn't notice until I was carefully checking so not easy to see. Shown in photos up close with and at a distance with red sticker over the damage. It is in otherwise very good condition. It also has, what I