If you are desperate, buy it off FM. However this can be very hard to find and if you do find it, it will cost a fortune as you must 'Karma' it to enable trading.
That is the Andras Hat. If you're an Aran, Dawn Warrior or Warrior you can get it by doing the chain of quests that probably start with Dances With Balrog.
go to hiddenstreet it gives informatie about all maple items also bowman
Do a series of missions( you know its the right one if it starts with perion getting no water) and in the end, take a quest and fight Dances with Andras. He has 5,000 HP, and his attacks do about 100-300 damage. Beating him gets you 5,000 exp.(the quest, not Andras) and you also get the Andras Hat(only level 18+ warriors can put it on)
Kill Scarlion.
zakum helmet
Yes.
Purchasing a Disguise Quest...
You can only buy them from the Free Market or the MTS
Same way you would with any thiefs.
The woman that wears the white stuff, and the hat with a blue W on it.
Go do Kerning Party Quest or do Maya and the Weird Mediciene
Only thieves can receive the Valefor hat. You obtain it after completing the quest, 'Catch Valefor!'