It would fit a range of sizes.  It measures approx 9 inches across the bottom of the neck and approx 3" deep on each side of the neckline.  The arm opening measures approx 7 inches across and the bottom opening is approx 20 inches across.

Good vintage/antique condition, usable piece.  Please see photos.  It has some light age darkening in spots, but it really looks natural.

Buyer to pay shipping.  I will package carefully in a box and ship promptly.