Sadly, I have not served in the military, so my limited experience with gear might not be the greatest information, but I hate seeing a post go with no replies. Especially a post made by someone headed to the box.
These are my suggestions based off of my research and experience:
1. Go with the Oakleys. You can get a killer discount if you contact Oakley directly.
2. It gets pretty cold in the Middle East, but since you're going in the summer, the UA HeatGear would probably be better. You can pick up a lower-end equivalent at Target or Wal-Mart for a fraction of the price.
3. No experience on the boots, so I couldn't tell you. Everyone will probably tell you to get Danners anyway.
4. From what I understand you should be issued two Camelbaks. I've read that a lot of guys don't use them because there is a ton of bottled water, which is apparently more convenient.
5. Don't know about the Ear Pro.
6. Batting gloves, Mechanix gloves, and gloves from Southwest Motorsports are highly regarded.
7.I'd suggest the Rolly Poly. I'm sure it will come in handy.
8. G2 should be enough. However, I understand that you don't usually need something blindingly bright, so you'll want to pick up some Photon LED's or the equivalent.
9.
Read the post by Stephen, halfway down the page.
Edited to add: You'll want to have someone send you a buttload of chewing tobacco. It's like gold. You can trade it for anything.
Good luck. Be safe. Our prayers are with you.