You'd need 138 g of potassium hydroxide to produce that many moles of potassium sulfate.
The balanced chemical equation for this neutralization reaction looks like this
Notice that you have a
In other words, regardless of how many moles of potassium sulfate are produced, the reaction used up twice as many moles of potassium hydroxide.
Since you know how many moles of
To get the mass needed to deliver this many moles to the reaction, use potassium hydroxide's molar mass
Rounded to three sig figs, the answer will be