Could try other outdoor folks too. I have a coworker I give a 5 gallon bucket of black walnut every year.
Been collecting buckets of pignut hickory in hopes of having a few take off up at camp. Hoping to have some grey squirrel come over to the property someday. May add some pin oak this fall up there too. Doing the pignut hickory because it grows faster into seed production, and the turkey and deer dont hog them up on the squirrels.
What kind of volume your looking for on here? Also, ebay has all sorts of nuts, seeds, and scions for sale. Sometimes you get lucky.