Or search: talker, speaker, utterer, stammerer, verbaliser, verbalizer
2 Syllables: SU
buckler, jugglers, smugglers, subtler
3 Syllables: SUU
customer, muscular, sufferer
4 Syllables: USUU
discoverer, stenographer

Found 9 words across 3 groupings. Skipped 3 excess words of a similar stem.