I think I'm lucky in that I have a fairly local supplier of what appears to be very good feed from Tucker Milling in AL. I started out with Alabama Co-op feeds because of ease of acquisition and the price being right, but after looking at the ingredients, I felt that their feed was geared more towards big farm production birds and not the backyard flock enthusiast.
When I first found out about Tucker Milling I was going to try a bag of their starter feed but the store did not have any unmedicated feed, but did have the non-GMO variety. A little more expensive, but ever since opening the first bag I have not swapped over to the cheaper version. I mean the stuff even smells delicious to me. My cats try to eat it if they get near it and my dog certainly tries to get hold of it.
At $15/50 lbs its a steal imo.
Looking ahead, they have several different layer feeds, from 16% protein to up to 22% (have not priced that yet)!
https://tuckermilling.com/flock/