If they've go to be just5 letters and no more??....
chert,chirp,chirt,choir,chore,coper,crept,crypt,epoch,hoper,hyper,ichor,itchy, ochre,optic,perch,piert,piety,pitch,pithy, porch, potch, price, pricy, recto, repot, retch, rotch, their,throe, thorp, toper, topic, torch, trice, tripe, trope........ etc All in Chambers Dictionary