I have just had a proper look at it and here are a few things that may be of interest.
The sleeves are of a different fabric to the rest and there is a black band on the inside of the sleeve, about 2 inchs wide around the bottom of the sleeve.
There is a seam that goes from the armpit to about 3/4s og the way down the front side, in a curve then stops.
There is also a seam that goes from the armpit to the bottom of the shirt in another curve at the back.
If you have a head like Dutchman, you may struggle, as the neck opening is a.bit tight.
If you want more photos just let me know and of what part.