Is there

[Aaronock]

Vane Hairpin [1]
*Vane shaped hairpin. You can find the velocity of the wind with this?
AGI + 2
Impossible to refine this item.

This one will look girly as hell on you but it does meet the requirements of what you're looking for.

Another hatter hat you can try for is this one.

Tailring Doll Hat[1]
*So hot! A headgear with the figure of Kafra Telling! She is such an active and hard-working lady. So she became the most favorite Kafra among users.
+2 Agi
Reduces damage from Demihuman monster by 5%.
Increases the effectiveness HP using potion pitcher by 10%.
Impossible to refine this item.

It doesn't mention the +2 agi on the description but the code says there is +2 agi and the heRO hat I believe fixed the description to include this bonus.