I'm sure you know you should replace your bracers. Every tank in my guild has Minion Bracers, (trash drop from Naxx) at least, with the exception of 1 DK who has the Bracers from H AN. Trinkets look good, you def need to lose the Blue ring, which should be pretty easy if you're running naxx frequently as every other boss has a chance to drop a ring. My personal fav is the sand worn band. You def need to get to 540 defense if you're going to be tanking raids, so maybe throw a 12/16 def gem, or switch to a shield with a bit higher defense. Hope for the upgrade to the seal of pantheon drop from naxx...think its called repelling charge? I don't remember, I have it on my pally. But I still use the essence of gossamer. 111 stam is too much to leave behind.
Heres my armory -
The World of Warcraft Armory