Stacker rhymes with:
attacker, tacker, acker, aker, akre, attacker, backer, bakker, blacker, bracher, bracker, cracker, hacker, lacher, lacquer, macher, makar, packer, racker, sacher, schacher, slacker, tacker, thacher, thacker, thakkar, tracker, vanacker, wacker, whacker, zacher
Stacker sounds like:
satcher, scheidecker, scheidegger, schweitzer, seducer, setser, setzer, shatzer, sight-seer, sightseer, sitzer, soothsayer, stachura, stager, stagger, staiger, staker, statzer, staudacher, stecher, stecker, stegar, steger, steiger, stetzer, sticker, stickier, stiger, stitzer, stocker, stoecker, stoeger, stoker, stucker, st_cyr, sweetser, sweitzer, switcher, switzer