That sounds beautiful! Places like Prairie Moon Nursery sell seed in bulk, but it's better to find local sources if possible. iNaturalist can be good for this. You'd have to look up when they go to seed and be mindful not to over harvest.
Personally, I would test the waters with landscapers using common blue violets and native wood sorrels since they aggressively spread themselves. They can handle a wide variety of conditions and mowing.