Hi... Here's a list of items that I have gathered/currently gathering for myself...
From the gear I see you have posted so far I'm guessing you are not yet raiding in ICC... Unfortunately you have quite limited options as to upgrades just running through heroic instances.
There are some gear you could get from Naxx/Ulduar/ToC but I wouldn't recommend putting the time required for it now that we have the 15% Health Increase/Healing Increase/Damage Increase in ICC.
Might be tough going ICC right away but going a few weeks in the first wing should get your group some nice gear fairly quickly + it makes the Frost Badge farming faster.
Lightsworn Chestguard T10 chest is a good option but a temporary one at that... The Cataclysmic Chestguard is a lot better. More Strength/Stamina, an additional socket, higher armor value. The only reason I went with T10 when I did was due to the 4 set bonus... Which isn't that much of a deal in ICC due to the dodge debuff.
Black Spire Sabatons is an ok option untill you reach the point where you can craft/buy the Boots of Kingly Upheaval
Neverending Winter Drops from the Gunship Battle encounter in normal ICC 10 man version.
It's, if not the easiest, one of the easier encounters in ICC.
If that's not an option at the moment then Barricade of Eternity from Malygos in Eye of Eternity might be a good, temporary option.
Bulwark of the Royal Guard is another good shield due to the socket and drops from Anub'Arak in ToC 10man NORMAL MODE.
When it comes to rings there are a few options. You can get the Titanium Earthguard Ring which can be made from a jewelcrafter. You can get Clutch of Fortification which is buyable for 35 Emblem of Triumph. Or Ashen Band of Courage which you get by doing a quest in ICC... This is quite easy actually but might take some time at first. You farm reputation by killing the trash mobs up to the first boss... Run outside, Reset and enter again untill you reach FRIENDLY. This ring can later be upgraded when you are HONORED, REVERED and EXALTED.
You are gonna get this ring at some point so it's pretty much this ring + one of the others.
Abomination's Bloody Ring should also be quite easily obtained as it also drops from the Gunship Battle encounter, Same as the Neverending Winter shield.
When it comes to trinkets there are two, easily obtained trinkets you can go for right away.
First one is The Black Heart which drops from ToC 5man NORMAL MODE from the end boss.
The other one is bought with Frost Emblems Corroded Skeleton Key
I hope this helps a little bit