Buy a (perhaps used) Android e-reader, e.g by Sony or Onyx, and write an app for it. Still easier, do without the app, instead point the e-reader's browser to a

Buy a (perhaps used) Android e-reader, e.g by Sony or Onyx, and write an app for it. Still easier, do without the app, instead point the e-reader's browser to an auto-updating web page which you host in your LAN on a raspi. (Or, if you are courageous and keep it really simple, perhaps even on an esp32 e.g. running micropython.) Edit: OK this is not exactly the approach you requested, as the e-reader does not really run Linux. But it works :)