Or search: swag, treasure, worthful, expensive, priceless, semiprecious
3 Syllables: SUU
annual, fallible, gradual, malleable, manual, palpable, valuables
4 Syllables: USUU
Emanuel, Emmanuel, impalpable, infallible, invaluable

Found 12 words across 2 groupings. Skipped 2 excess words of a similar stem.