I run a cheap android head unit in my 4RUNNER and the quality is horrible. The only reason I got it is for the pratical side of it (gps navigation offroad with phone apps, etc.)

The unit I have right now doesnt have enough RAM (only 1GB) and its super slow. I would be ready to pay twice what I paid to get a quality one with good hardware like a decent processor and lots a RAM but I did not find anything good online when I bought it.

Will still keep it because I am now used to the pratical side of it. But if it ever dies I wont be trying to fix it. Ill try to find something better still android based.

Right now I have a Joying head unit and I would probably go with a Insane Audio FJ1001 next just because its overpriced and I hope it means quality... Insane Jeep Audio - Insane Audio In-dash Navigation and Multimedia Entertainment System - FJ1001 | 4WheelParts.com

That looks oddly like one of the JOYING units

I now run this Sony Android Auto head unit which works great.

Go to a Toyota dealer, they have he wiring diagram books for every model. Those books show exact wire color and pin out of all wires in the whole vehicle. If you are talking about the wires that go to the ecu then that will be more money. Dealers have the factory wiring repair toolkit with all the right metal connectors as well as solder, heat shrink tubing and metal crimps to fix harnesses. I was a Toyota tech for 10 years so I know what I'm talking about. Either way if it is just some disconnected wires it should not be very expensive, even if someone had cut the plug off for the ecu it still is only about 50 wires so a few hours labor and some materials could run you maybe 600 or 700 bucks at the most UNLESS THERE IS MORE THINGS THAT YOU