Is there an easily accessable basic sweet feed that doesn't have a risk of ionophore contamination? The all stock sweet feed that I typically see makes me nervous.

What feed brands can you get in your area? Bluebonnet Feeds is the only one I trust, and have been using this feed company for many many years.

I'm in ND and all we have locally is a Runnings and a TSC (and a local mill but I don't like them) or I can order from Chewy so I can get the typical brands like Purina, Nutrena, Buckeye, Dumor, Producer's Pride, Triple Crown, Tribute, some Bluebonnet... 

I see that chewy is carrying some of BlueBonnets sweet feeds and those are all good feeds, I feed only the pelleted feeds of bluebonnets, I do buy the versatile sweet feed for my really old donkey this is the only thing he really likes so he gets it. You can go to blueBonnets web site and look up the NSC% on the feed that Chewy does carry of BlueBonnets, and I have bought horse feed from Chewy and it was so fresh, I could not believe how fresh it was.. But the Pelleted feeds of Bluebonnet is great and better. 

Since you live near a TSC, my best bet would be Triple Crown Complete. Its on the pricier side, but I've heard many amazing things. Triple Crown also comes from safe mills.

I've tried Omolene 200 (Purina) before, and my horses got really hot on it. It is also not a healthy choice. I use Race13 on my Racehorses, but because of your living situation it might not be available.

Isn't Triple Crown made by Blue Bonnet?  or am I mistaken? 

I know they make another line of feed... 

I believe it varies on where your from. I know many Triple Crown Feeds are milled by Bluebonnet or Purina. Some are milled by blue seal aswell. It varies...

This^^^^^

Nutritionally, basic sweet feed is the most expensive feed that you can buy. You need to understand that there is simply no cheap way to make a feed that gives you your moneys worth if you want nutritional support. Cheap sweet feed is always least cost formulated with the lowest quality (cheapest) level of any ingredient that they use. Lowest quality and rain or storage damaged grains are used that you would never feed if it was not hidden by molassas so that you can't actually see it. 

Y'all know that I am basically anti grain for horses. Lot's of people can't get their arms around that, and I understand. If you simply feel that you need to feed grain, just buy some oats. At least you can see what you are feeding. Do not feed anything with corn, wheat or soybean meal. Also, stay away from any label that lists "forage byproducts" or anything else that is vague in its discription. 

Save the money that you send on cheap sweet feed and spend it on better hay instead. You will be way ahead.

Remember, When horses were evolving, there was no place that they could stop at the grain pile, and their digesive system is not designed to properly digest very much of it.