I found an $50 micro projector on ebay that has a USB power output. The 480 resolution is plenty for all the game systems! Fits perfectly below the MiniNES case!
I do get undervoltage warnings, but I should be fine as long as I have a clone image to use when my SD card goes corrupt. Here is the link if anyone wants to take a chance on a “untested” “might be broken” “sold as-is” “no power cable included” projector