I have been using this screen from Sunfounder. It is intended for use with a Raspberry Pi. It powers from 12vdc and supplies a USB 5vdc connection to the Pi solving the problem of how to power the Pi from your 12v battery. Comes with all the cables and a 12v wall wart.
It seems to be a good size, and works okay. You still will have trouble in bright sunlight, but a shade could be built pretty easily.
https://smile.amazon.com/gp/product/B07SZH1VB2?psc=1
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Al AE2T
