For all of you unable to run a normal raid and unsure what to spend Warforged Seals on, here's a list of what your top priorities should be. Take a look at your gear and see what pieces need replacing.
-Head - Tier helmet is dropped off of Thok the Bloodthirsty, in The Underhold. Run The Underhold on LFR until you are ready to run it on flex.
-Necklace - Look into flex drops or use a Burden of Eternity from the Timeless Isle until you get a flex drop.
-Shoulders - Tier shoulders are dropped off of Paragons of the Klaxxi, in Downfall. Run Downfall on LFR to get the shoulders and then run it on flex when you have the gear and party to do so.
-Chest - The Tier chest-piece is the most accessible to you since it drops off of the Sha of Pride, in the Vale of Eternal Sorrow, therefore, you should probably shoot for the flex version of this piece first, and try for the LFR version as a fall-back.
-Bracers - Look into flex drops or use a Burden of Eternity from the Timeless Isle until you get a flex drop.
-Gloves - Tier gloves are dropped off of the Celestials on the Timeless Isle.
-Belt - The best belts, outside of Ordos, can be made by either a Blacksmith, Leatherworker, or Tailor. So, try to negotiate a price with someone who has these professions or check the Auction House if you don't know any.