Hearthpwn

Outrider's Axe -> Mor'shan Elite

Terrorguard Escapee -> Earth Revenant

Headhunter's Hatchet -> Ratchet Privateer

Sword of the Fallen -> Northwatch Commander or Crossroads Gossiper

Death's Head Cultist -> Plaguemaw the Rotting

Frankly, I think there's a reason this line of exploration is hardly explored. I'm pretty sure it's better just to have a good three drop and a good four drop than a mediocre three drop that likes to be followed up by a specific mediocre four drop.