If that isn’t panning out, you could reach out to local landscapers who specialize in native plant design and offer them a good deal, especially toward the end of the season. They may have jobs spec’d that they still need to fill, or be willing to design around what you have. In any case, I hope you can find good homes for them!

Have you kept track of the species and approximate quantities of each? A solid spreadsheet or inventory list that you can circulate to nearby groups or organizations would probably drum up more interest than random pop-ups or sales.