Answer: Here are some suggestions:
mock orange 'Dwarf Snowflake' (2-3' tall), or 'Galahad' (4-5' tall)
potentilla 'Primrose Beauty' (2-3' tall)
dwarf flowering almond (up to 7' tall, but can be pruned to 5')
Rhododendron yeodense Poukhanense (3-6' tall depending on cultivar)
dwarf or semidwarf lilac, such as 'Josee' or dwarf Korean lilac or French hybrid lilac 'Little Boy Blue'
There are also some viburnums that would fit the bill.
All of these are available from Carroll Gardens, 1-800-638-6334
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