1 syllable:
-trix, brics, bruck's, brucks, buchs, buchse, buck's, bucks, bucs, bucs', ce ics, chics, chuck's, chucks, clucks, cn ix, crux, decss, dekes, duck's, ducks, ducks', dux, f/a-xx, flics, flux, fluxx, frics, gluck's, glucks, hp-ux, hucks, hux, hv mix, klux, knucks, luchs, lucks, luks, lux, lv mix, maccs, machs, mc cs, mc ps, mc ss, mucks, nsa css, nwa cs, peixe, pluck's, plucks, pucks, recce, rucks, rux, schmucks, schnucks, shikse, shmucks, shucks, sucks, szucs, tcf ics, tp ix, truck's, trucks, trucks', tucks, tuks, tux, yucks, yuks

2 syllables:
acrux, aw-shucks, blackbucks, bushbucks, calmucks, canucks, conflux, construx, delux, deluxe, dumptrucks, dybbuks, gacrux, horcrux, influx, jumbucks, kalmucks, karluks, kaunakes, mamluks, nunchucks, potlucks, reedbucks, roebuck's, sawbucks, shelducks, starbuck's, starbucks, swagbucks, upchucks, waesucks, woodchucks

3 syllables:
dinotrux, erbitux, geoducks, gerenuks, megabucks, metalsucks, neutron flux, supertux

4 syllables:
luminous flux, magnetic flux, marimbalax, milwaukee bucks, radiant flux