For your last item either grab a Guardian Angel or a Hexdrinker i wouldn't know cause i have never had a game long enough on irelia for me to get a 6th item.

Irelia

The Will of the Blades
Attributes Assassin, Carry, Fighter, Melee, Nuke, Slow, Stun, Tough
Release Date November 16, 2010[1] First Free Week TBA


Statistics

Health 575 (+85) Mana 265 (+35) Damage 56 (+3.3) Attack Speed 0.665 (+3.16%) Range 125
Armor 19 (+3.7) Magic Res. 30 (+1.25) Health Regen. 6.5 (+0.65) Mana Regen. 4.5 (+0.45) Mov. Speed 330

Cost: 6300 or 975

Abilities

Ionian Fervor Each nearby enemy champion (to a maximum of three) reduces the effectiveness of Crowd Control on Irelia.
���¢�¯�¿�½��� 1 Champion: 10%
���¢�¯�¿�½��� 2 Champions: 25%
���¢�¯�¿�½��� 3 Champions: 40%
���¢�¯�¿�½��� Range: 1300 (estimate)

Ability Description

Bladesurge (Active): Irelia dashes forward to strike her target enemy, dealing physical damage. Applies on-hit effects, but cannot crit.
If it kills the target, Bladesurge's cooldown refreshes and refunds 35 Mana.

���¢�¯�¿�½��� Cost: 70 Mana
���¢�¯�¿�½��� Range: 650
Cooldown: 14 / 12 / 10 / 8 / 6 seconds
Physical Damage: 20 / 55 / 90 / 125 / 160 (+1 per Attack Damage)


Hiten Style (Passive): Physical attacks restore health.
(Active): Irelia's physical attacks deal additional true damage for 6 seconds.

���¢�¯�¿�½��� Cost: 40 Mana
���¢�¯�¿�½��� Cooldown: 15 sec
Heal: 10 / 14 / 18 / 22 / 26
True Damage: 15 / 30 / 45 / 60 / 75


Equilibrium Strike (Active): Irelia pierces her target, dealing magic damage and slowing the target by 60% for few seconds.
If the target has a higher health % than Irelia, she stuns the target for the duration instead.

���¢�¯�¿�½��� Cooldown: 9 sec
���¢�¯�¿�½��� Range: 425
Cost: 50 / 55 / 60 / 65 / 70 Mana
Magic Damage: 80 / 135 / 190 / 245 / 300 (+1 per Ability Power)

Duration: 1 / 1.25 / 1.5 / 1.75 / 2 seconds


Transcendent Blades (Active): Irelia summons 4 spirit blades which she can fling to deal magic damage to enemies they pass through, and she heals for 20% of that damage.
���¢�¯�¿�½��� Cost: 100 Mana
Cooldown: 60 / 50 / 40 seconds
Magic Damage: 90 / 140 / 190 (+0.4 per Ability Power OR +0.6 per bonus Attack Damage)