Where can I get a radio that is suitable for someone with dementia and vision problems?

I have alexa and I just tell it to play acoustic blues (or whatever) for 45 minutes.
I can also schedule music to be played automatically for certain times when Mom's awake.
My mom cannot work the radio, or any electronics.
I tried the one button radio and she wouldn't use it.

That's a tough question to answer. With dementia, she cannot learn how to operate a device for herself. Perhaps the caregiver can play the music. One with a sleep timer is best to save batteries/power.

There’s a one button radio available. You preset the station and the volume. All your loved one has to do is push the button.

https://www.maxiaids.com/one-button-radio?gclid=CjwKCAjwhuCKBhADEiwA1HegOSgmgXNenoPOvJCuDxSBHhkcM76lkQh46fHMyScPuaL96w6LMCI2PxoC86MQAvD_BwE

Get an Amazon Echo Silver.

Your LO is 100 years old. The odds that she can remember how to use a new piece of equipment, no matter how simple, is probably not good with her cognitive and vision problems. If you do get her something, it would be for the caregiver to turn on and off and find channels for her.

Here's a music player that's easy to use.
Just download songs from Amazon or iTunes onto this player. And they can listen anytime.

https://www.amazon.com/iGuerburn-Upgraded-Dementia-Products-Alzheimers/dp/B08D3LJQG2/ref=mp_s_a_1_3?dchild=1&keywords=mp3+for+seniors+with+dementia&qid=1633133960&sr=8-3

I think that would be hard because with Dementia they forget how to use phones and remotes probably will not be able to learn how to use a radio. The only thing I could suggest was an Alexa or something like that.