1950s or 60s vintage dead stock NOS deals McGregor Italian collar shirt jac M

Late 50s or early 60s McGregor shirt jac with an Italian style collar. This is never worn and still has the tags attached. The fabric is textured and the label says it is 90% rayon and 10% silk.
The shirt is in excellent condition. There are no stains or musty odors.
The shirt is marked size medium. The measurements are:
22” chest laying flat pit to pit
18.5” shoulders in back
25” length from the top of the collar down in back deals