Most importantly, thank you for serving our country! May God bless you for your sacrifice.
I am headed off to Pennsic War in a couple of days. While there, I will be camping with a group of brewers from the New York area. We have meads and wines on tap for the two weeks of Pennsic with excellent results.
We use CO2 to pressurize. The beverages are stored in old cornie (soda) kegs. We use a chill plate in an ice chest to chill the drinks as they are served.
You just really need to make sure that your fermentations are done before you keg things. A keg will not stop fermentation although pressure build-up will stunt a fermentation a bit. But in the end you can have a "bottle bomb" that hurls sharp shards of aluminum around the room.
A few years ago we had a ten year old Blueberry Wine brought back to our camp in a cornie. It had been kegged and given to someone three or four years earlier and then passed around but never used. Eventually the "Return TO" tag on the keg brought it back to the camp. IT WAS GLORIOUS! So in this case it had been in a keg under pressure for three or more years without any other special handling (and likely with some unfavorable handling like hot tents and storage places) and had managed to remain just fine.
The group I am with makes sure to keep everything under pressure. We serve at a lower pressure to prevent foaming. But for storage I am thinking that the kegs get pumped up to 50 or 60 PSI. (That may not be the right number.)
Good luck and again, thanks for serving,
Pewter