I've been running T-10 (251) head and shoulders on my Pally tank for the 2pc bonus. Also have the Cat chest, Pillars of Might, and Kraken gloves. Last night, I picked up the Heroic Gunship 25m shoulders, so I will have to replace one of the other pieces to maintain the set bonus.
I do have the 264 T-10 gloves from VoA already, but I could buy one of the other tier pieces if it would make a big difference.
If you want to keep the two piece bonus, with those options I'd use 264 T10 Gloves and the helm you have, with the Gunship heroic shoulders. Alternatively, don't bother with the 2pc bonus on fights in which you don't need the threat and use tier helm, Kraken and off-set shoulders.