How about a black spirit gift of sorts...
Once you extract an armor piece with more than c10 level of chaphras, the black spirit gives a gift of [honor] version of the piece.
This would circumvent the whole creation and location binding of new dailogue options with other NPC's.
That could work too, would make it a lot simpiler. or giving it through the main questlines as well.
Why not a Title unlock ( Killing 100 time Dim tree spirit boss field) You got the Title -> black spirit offer you the Outfit.
Or a new item from these boss. You get 200 of them and you can craft the outfit in a costume mill.
it would just be more fun if the way to get the outfit was a relationship with their bosses to be more in some logic.
With the addition of Lebreska Helmet, I think now would be a great time for the additions of Honor Armors for Helmet and Chest pieces since almost all the only armors are getting phased out, and their cosmetic side along with it.