craft daul weapon

Hi guys, let me ask you a question

It will be my first time to craft a dual weapon and there is one thing i don't know.

Specter Shaper 2

Crystal (R-grade) 15156



Dual Weapon Crafting Stamp (R-grade) 1

Adena 378898400



About this 'dual weapon crafting stamp' do i have to buy/find it from somewhere or when i have rest of the stuff (daggers+crystals+adena) it will automaticly turn into R99 dual daggers?



ps. and i am not dwarf, if there is any difference of it.