They do have ones with their logo on cerain beers. I think I got one off of my last bottle of ba ist. If you can't find one let me know I should be able to get you one without much problem.
I stand corrected..... All the brewery releases I have in my cellar have generic caps; but IST had a New England logo cap.... If you still need one I can hook you up after Monday when I plan on drinking my IST (May the 4th be with you....)