I got it from c0pperdragon on Tindie. They don't make/sell them anymore, but the designs are public in case you want to build your own.
I want another one myself, but I've been hoping someone else might pick up this project so I can just buy one instead of ordering custom PCBs, sourcing all the components, finding out a bunch of them are not compatible, ordering more components... you get the idea (or if you've done this before, it's more like "you know the drill")
Making sure you're not a bot!
GitHub
GitHub - c0pperdragon/HotPlate
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