If you're really interested in that shirt, PM me and I can put you in touch with the fellow who supplied a lot of the wardrobe for Shutter Island. Last time I saw him, he had a lot of the clothes from the film back in his store -- he'd just sold someone the hat that Ben Kingsley wears in the movie. Amusingly, that was the same hat he'd worn all the previous winter, before the film people stopped by. It's possible that he either has the shirt in inventory or can give you details about it.