I've got a £50 dumb nokia phone, it's lighter than any smartphone and last for 1-2 weeks on battery (it's about 5 years old), impossible to break, i never have to think about it or worry about it, it doesn't distract me until someone really needs to communicate with me... I love it, but then I never liked smart phones.
Call quality is really good.
On Amazon, search by carrier, sort by lowest price. Some are low end Android, but some are feature phones. In my experience really low end android phones have such little storage they might as well be feature phones. You could only get 1-2 apps on max if you tried.
Amazon lists at least one more but look at the fine print, if it's a 3G model it can't be activated after the end of 2018.
In the UK i can just buy any unlocked phone I want online and stick my sim card in it, the networks let you use whatever you want. My current phone is only 3g but this has worked everywhere I have traveled so far, Europe, Asia, Mexico, but not tried US.
Then best part about the phone is that I'm not tempted to pull it out of my pocket and check social media or browse the web every minute of the day.
It's also one of the smallest phones on the market, fits in the hand and pocket much better than every other phone.
I also have data completely disabled on it. I haven't changed my phone plan yet because I wasn't sure I would be happy with the phone, but Ive been using it about 3 months now and thinking of downgrading to a $10 a month plan.