Poultry feeds vary a lot in different parts of the country and the prices are all over the board too. I've read where some of the breeders are able to find $7/50# feeds, but that is not the case in our area. You can find the national brands but sometimes can find a cheaper ration from a local mill. The trend toward the "Natural" feeds has brought a lot of diverse products on the market and most of these will cost a lot more than the regular feed mill rations. Finding sources that are Non GMO and organic are often hard to locate and will certainly cost much more. You can more likely be able to find an independent grower that can supply grain directly at a more reasonable price, but you will be limited as most growers don't plant many types of grains in a single year. Sarah Meaders uses a ration of grains that she can adjust depending on what grains are available at that time. The other option is to use a base commercial ration and supplement this with special minerals and vitamins to enrich the diet and bring the protein up higher a bit. Poultry are omnivores and like a variety of grubs/bugs. This type of protein is not available in a lot of the "Natural" feeds as they base their protein on mostly soy products, no animal protein. A higher protein especially animal proteins are helpful to provide a wider range of nutrients for breeding/hatching. Some will use scrape meats from hunting/processing, meal worms or even fish or cat foods to better these diets.
There is a lot to discuss on the subject and there are Many different opinions as well. Feel free to ask specific questions as you go thru your search and learning curve. Hopefully you can help the rest of us along the way. You can search the forum for feeds and rations to find some other discussions thru the years too.
Good Luck and Enjoy!