It can only be bought in Balnuunla in LF2.
Have you started LF3 yet? If not you might want to go back to your last save file in LF2 and buy it. That Elven Half God sells it in his weapon shop.
And if you want to do that you might also want to buy two or three Tiki Tikoo Suits cause they're great and in LF3 you'll have 3 characters who can equip it.