Long time lurker, first time poster, really enjoying this forum and the game!
I have a witch hunter themed warband with witch hunter models for marksman and captain. I use crossbow rules for pistols (1 action reload, +2 damage). One of the minis I use are from avatars of war, the witch hound (no link, sorry) as captain with some sweet double crossbow action going on, and scibor miniatures vampire hunter
http://www.sciborminiatures.com/en_,shop.php?art=1373 for my marksman. The demon hunter would be a great thematical addition to the warband, one could use the gw witch hunter for instance
https://www.games-workshop.com/en-NO/Empire-Witch-Hunter if the crossbow=pistol does not bother you.
I do not have the fp expansion yet (we've just started on the lich lord), but I've seen the stats for the hunter somewhere so I know they are armed with crossbow and great weapon. Is there anything else about them?