I spent a few years living in a developing country in Africa so I have some appreciation of what you’re going through. I used to find lots of technology shops on Google Maps, etc, then when I got there they just sold phone covers and SIM cards and knock-off iPhones.

I can’t really offer much advice but have you considered just making something based on a second hand laptop? A lot of them are still pretty powerful just with old batteries and they’re designed to run efficiently.