The closest I can offer to what you’re asking for is that there are some e-readers that use Android. I own a Boox Page, which is one of those, and I’m happy with it. Boox products are a bit on the pricier side, but they do offer features that can be difficult to find on other manufacturers’ offerings, such as a micro SD slot.
I have a T480 that I’m very happy with. With shipping I paid a little under $250. It came with 16GB of RAM and a 256GB SSD (which I replaced with a larger one).