Post's rhymes with:
posts, boasts, coast's, coasts, ghosts, host's, hosts, jostes, posts, roasts, toasts
Post's sounds like:
packets, packwood's, pact's, pacts, pagoda's, pagodas, pas-de-deux, pastas, pastes, pastiche, pastiches, pasts, pectic, pesetas, pestka, pests, phagocytes, physicists, piaget's, pickets, pickett's, picts, pistachio, pistachios, pockets, posits, post-attack, postage, postdates, posts, psychotic, pussycats