The Typeframe is modeled after the Epson PX-4 and looks like a twin. The 7.9" LCD is also a touchscreen. I chose a Raspberry Pi 5 and an inexpensive ready-made keyboard. It's all powered by a 10 Ah battery and charges with USB-C. And lots of 3D printing and cable management.
More info. to build your own: https://www.typeframe.net/