I got it for about $40 a year ago, but it looks a bit more expensive now ($90 on Amazon). It was a bit of a pain to root it, but I was able to follow some online guides - I've been meaning to publish a repo with exact steps. Let me know if you order! There are a couple similar phones that work well, the important thing is getting AOSP and not other firmware.
I'm looking at a number of options, mostly those recommended at /r/dumbphones on Reddit. There are the Lightphone II, Mudita Kompact, and Clicks Comm there.
Elsewhere: Punkt MP02, Kyocera Dura series, Cat B22 / S22, and a few of the Nokia / HMD phones, preferably flips.
Most are AOSP, HMD/Nokia are S30+. KaiOS also turns up (an AOSP variant).
What other firmware don't you recommend?
And what was your primary motivation? Just simplifying your phone, or security /privacy / other on top of that?