Barba Napoli 14.5/37 white shirt - $100 shipped in the Con US
Across back: 17"
The shirt has darts through the torso which really adds to the fit. I would say it's a slim/extra slim cut.
Only been worn about 3 times, it was my preferred white shirt for extremely nice occasions.
Some quick pictures, sorry it's not ironed and folded just yet:
Here are some more full length pictures, getting PMs to see the whole thing: