Hearing damage should be on the easier to show side; I'm sure they screened your hearing during enlistment, so if your hearing tests as damaged when you're discharged, there you go. Confirming a connection to service if you don't test near discharge might be harder.
You might be surprised... a friend of mine spent 18 months in a tank with a cannon next to his head and has almost total loss in one ear and much lower function in the other... he's had trouble getting VA to pay for hearing aids.
I'm sorry to hear that; I would have expected it to be much easier than some of the stories I've heard about getting coverage for Agent Orange exposure from family and others.
