Some of the smaller family run mills will mix feed in smaller batches. The one I get my feed from has a minimum of 300 pounds for a custom mix. I get half a ton at time now and they mix it exactly the way I want it. All the ingrediants are always in stock as they are used in just about every animal feed out there. Even the Fertrel's Nutribalancer and probiotic mix is always there. It took me a good long while to find this mill and I drive farther to get my feed from them. Their service is great and they work with you. A good mill might not be cheaper (it can be though, 50# of feed was roughly $11.25), but it sure makes life easier.