Trinity shield
Sheen(1200g)+ Raptor Cloak(1000g)+ Quicksilver Sash(1250g)+ some change(200-300g?)=
Trinity Shield 250 mana 30 ap 50 armor 50 magic res
Unique Passive - Spellblade: After using an ability, your next basic attack deals 50% base AD(+6% of target's current health) bonus magic damage.
Unique - Point Runner: Grants +30% bonus movement speed that builds up over 2 seconds when near turrets (including fallen turrets).
Unique Active - Quicksilver: Removes all debuffs from your champion. 90 second cooldown. (Could also grant +50% movement speed for 1 second.)
:D
Edit: another option would be replacing sheen with catalyst;
Trinity Shield(version 2) 300-400 health 300 mana 30 ap 40-50 armor 40-50 magic res
Instead of spellblade passive, there would be Valor's Reward: On leveling up, restores 150 health and 200 mana over 8 seconds.
Mikaels crucible, which also heals as well.