The website always find is the one where you customize your items. I believe it's official, but year, it's customizable.
If you're in New London at all, you CAN get on academy grounds and you ARE able to buy things at the Exchange (the academy bookstore is in Chase Hall and typically off-limits). You're able to purchase CGA and USCG apparel. I can't remember what I did, but I'm guessing ordering online wasn't an option so we just called. If you want something from the Exchange, I'd just call them and see if they can at least describe what they have. You may want to narrow it down for them a bit "I'm looking for a sweatshirt with the academy crest.... for a male, size...."
I still have my CGA sweatshirt that I got while I was visiting CGA in high school, after I had been accepted.
Of course, once you go there, those things are considered civilian clothing, and you won't be able to wear them much for a couple years... nor will you want to, since you'll be bathed in CGA blue 24/7 and you'll just want to "escape."
I don't think CGA does the best job at making its gear available, which is unfortunate because some fo the stuff at the Exchange is really good. The only thing I'd REALLY like for them to make is CGA hats (where the C-G-A overlaps) in "Franchise" hats (they're like fitted hats, but more general sizes, and really relaxed fit/construction).