Here is a terrific looking short sleeve polo shirt by Screen Stars. 50/50 poly and cotton blend and made in the USA. Could be from the 70's, but I'll call it 80's. Bold blue shirt with a three button front and a pocket on the left breast. Feels like it's never been worn! Super soft, comfy, and in amazing shape. The tag says Small, but here are the measurements. (refer to the last pic above to see how I measure shirts)

I also have this exact shirt in green and in red if blue isn't your thing!

Chest (armpit to armpit) 18"
Shoulder to end of sleeve (including cuff) 9"
Length 28"

This item is sold from a vintage boutique in Roanoke, VA.