To add to this, I have a small Nikita’s Gift and have ordered Barbara’s Blush, Early Golden, JT-02, and Celebrity. I will be grafting a few more onto seedlings at my office, to be determined. There is some great information on different cultivars on a few threads, here is a good start Jerry Lehman's Orchard Fall 2017 - #22 by Barkslip
I am ordering trees from England’s and some scions from fruitwood because I have some other stuff coming from them. England’s also sells scions. Pikes Peak in Indiana County sells 18-24" seedlings in packs of 50, I think $1.30 a tree. I will be picking up my order from them in about a week.