When I was there you needed four pair of the old PT uniform. They actually did come in handy as you cannot lounge in civvies at all in Nimitz Hall. Take what you have but I would report with at least two pair of the old ones and you can buy the other ones in the first few days.
BTW you get a uniform allowance and will be required to buy a full officer/OC/midn seabag. If you are smart you will bring whatever current uniform items that will carryover in good condition, such as:
Black Oxfords
Seabag
Peacoat
Raincoat
Winter Blue Pants (2), Tie, and Garrison Cap
CNT White Pants
Nylon Navy Briefcase
And anything else I'm forgetting but this list will save you about $400.
PM me if you want OC devices cheap or for trade