Measurements are approximate and the fabric allows for a little stretch.
Bust - 38"
I think it would best fit a modern day Medium or Large.
Measurements are taken with garment lying flat and then doubled. For the best fit, find a piece of clothing that fits you well, lay flat, and then measure just under the armpits (bust), at the smallest part of the waist (waist) and the widest part of the hips (hips) and compare to the measurements above.
Keep in mind that vintage implies that the items are used, and at least 20 years old. Vintage items are expected to show some minor flaws and signs of wear. Most items are washed before they are sent out and I do my best to note any flaws in the item description. Please read shop policies before ordering.