Chief2, I checked those out but can’t find a mini donkey model - otherwise that would have worked well.
Search for Heatherwear on Facebook. She is making fleece fly bonnets and I know she could do what you want! She made this for my daughter. It’s a fleece saddle pad and bonnet!
https://www.facebook.com/photo.php?fbid=10152709543328445&l=686ebdf172
Just message her and describe what you want. Incidentally, you can also get this…
https://www.facebook.com/photo.php?fbid=10152709539968445&l=1dbb709792
I have only ever seen a couple of cases of very minor frostbite damage to tips of the ears, both were foals.
‘We’ already drastically overblanket our horses as it is. Really, this is a need I do not see.
If I made one I would use an old fly mask as a template. I don’t know where I would get the material but maybe waterproof material on the outside, fleece on the inside, and follow the face portion of the mask but leave out the area around the eyes for visibility?
Beverley, I suspect I may live further north than you - closer to Hudson’s Bay than Utah. Frostbitten ears are not unusual here. I’m not at all suggesting that everyone should run out and put ear muffs on their horses (mine aren’t even blanketed and are just fine) but I think some sort of warm ear covers for our older donkey’s ears is not unreasonable nor overkill.
GranceLikeRain, thanks for the constructive input - that’s pretty much exactly what I want to try. Warm but waterproof for those times when it yoyos between freezing rain and minus 40! Our winters go on forever and the poor donkey could do with a bit of help.
I think the lady’s idea of using a winter coat from the thrift store was probably the best as far as fabric. They look adorable!
While you are at it, you will need two pairs, one to wear and one to dry! 
Whether it is absolutely essential for little donk to wear them is debatable - but an animal never suffered from being over cared for. Owner’s choice.
Just don’t leave a mirror out there for him to see himself.
[QUOTE=Mosey_2003;7953466]
I think the lady’s idea of using a winter coat from the thrift store was probably the best as far as fabric. They look adorable![/QUOTE]
I agree, or maybe if you could find a little kid’s coat, and just cut off the sleeves, sew up the tops and use those.
Sooner or Later, that’s a great suggestion. Thanks!
[QUOTE=luvmyhackney;7952232]
I actually found a site that had a diy for this idea. I just never got around to making them for my pony. http://www.shadowridgedonkeys.com/#!instructions-donkey-ear-muffs/c47l[/QUOTE]
I’d get kid’s ski pants and cut off the legs about a foot from the crotch, and cut an oval near the crotch area, so you have flat material with two “legs”. sew top of legs shut. Sew velcro to each end of oval, and Velcro under jaw to secure…
If I did that to my horse…good lord it would provide entertainment.
I think it’s great you care that much, and I think it’s great I don’t live anywhere that cold. 
Your summers must be stunning though.
Must admit, would love to see photos!
Update - after touring several thrift shops, discovered that small children wear out the bottoms of their snowsuits first… Came home with a stylish pink parka which I will try to fashion into to ear covers, using my zero skill set. Donkey is in his mid-cold-snap mode and has virtually stopped eating and drinking (I think his core temp gets too low after a few weeks of this). I carry warm water out several times a day and he will eat a warm mash but he needs to drink a lot more. My heated buckets both split last year from the cold so I think I will try to install a heat lamp in his stall for now. Even in my small insulated barn, with just three stalls, it’s cold enough that the water buckets have so much ice by morning that they can’t access the water.
Amarach, thanks for your kind words. He is indeed a much-loved donkey! Summers here can be beautiful but buggy, usually Sept. is the stunner of the twelve months. Thank God, because these winters are absolutely brutal. Will try for a pic of donkey with snowsuit sleeves as ear warmers…
Lucky little donkey.
In many places when there is a cold snap, horses will not drink the cold/ice water and end up with compaction colics. Ask any vet…So the warm water is a wise choice to encourage drinking.
Happens often enough when there is a drop in temperatures in not so frigid parts. When the barometer drops, time to check water intake. I don’t even know if the vets know why this happens.
