It is my understanding that you must be level 28 to scribe this quest. The item its self is NOT NO DROP so you can pay a low level group to kill him for you or buy it on the market, but I've not seen one on sale for less than 1pp on Mistmoore.
I have Stiletto's Orders and am level 26 and I could not scribe the quest last night. Is this not the beginning of the quest or does the quest start someplace else?