Here is a super stylish long sleeve button down dress shirt by Dunham's Store for Men, in Trenton. It's 65% polyester and 35% cotton. A rich dark blue accented by stripes of yellow, green, red, and maroon. 6 button front, and two front pockets. The tag says 15- 15 1/2, but here are the measurements. (refer to the last pic above to see how I measure shirts)

Chest (armpit to armpit) 20"
Shoulder to end of sleeve (including cuff) 25"
Length 30"

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