eBay
This stunning sportcoat is a recent model from Isaia Napoli, one of the top Italian makers of tailored clothing. It's made from their luxury Aquacashmere fabric, a blend of cashmere and silk, in a olive green color with a plum check that is perfect for fall. Two button front and double rear vents. 

The jacket is in excellent condition with no major flaws I can find.

The tagged size is 56 Regular (EU sizing); I estimate this to be around a 44 Regular in US sizing, but please see the measurements below for specifics.

Chest, armpit to armpit: 23" (46" total chest)
Shoulder width across the back: 20"
Length, from bottom of collar to hem: 31"
Sleeve length: 23.5" with about 2" to let out