I'm going to go out on a limb here without talking to T/C. But because the Hawken and Renegade locks are interchangeable I would bet a dollar to a doughnut that they used the same lock in the PA Hunter. That being the case I would guess that the double trigger from either of these models would work. BUT....there would likely be different inletting in the stock recess for the triggers and possibly a different trigger guard.
Probably a less expensive route would be to have your smith work on the single trigger to give you the pull you want.
On a side note - I prefer a double trigger also but most of the high end custom muzzys I've fondled come with single triggers. Must be for a reason!