Smith and Kraus publishes a series of scene books for groups of varying sizes. In 103 Scenes for 3 Actors, edited by Wilma Marcus Chandler, the table of contents breaks the scenes down by cast requirements - some for 3 men, some for 3 women, some for 2 men and 1 woman, and some for 2 women and 1 man. It has more than fifty scenes that would fit your parameters. I bought my copy from my local Barnes & Noble store, but Amazon has it available for $25.
Follow-up volumes include 104 Scenes for 4 Actors and 101 Scenes for Groups [groups of 5 to 11 or more].
Best of luck to you in your search!
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Jeff Grove
Theatre Teacher, Aesthetics Department Chair
Stanton College Prep
FL
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