If your looking for vendors that supply apple trees on different rootstocks you might consider Heritage Farm and Fruit Trees (https://heritagefruittree.com/) for apples as well as Cummin’s nursery. We have a nursery reference list on the forum which you might find helpful. It’s located here.
Sweet cherries are unlikely to be successful as a commercial crop in Kentucky as they need a very specific climate. We have a fair number of backyard growers on the forum that grow sweet cherries in the East but it’s a struggle. I would take a look at this thread to get an idea of the problems you would face.