Take some measurements first and then checkout the overhead consoles from other Toyotas.
One gen4's and later, there is a small compartment on the ceiling above the rear view mirror that has a door. You can store your sunglasses or if you change the door, you can store a garage door opener.
I wanted map lights, so what I did was to take this unit from a Toyota Tundra, enlarged the hole in the ceiling and mounted a unit like this, but different color.

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There are a lot of other overhead consoles with much more features that would likely fit. The key thing with units that mount flush like this one is depth. I thought about using a unit from a gen5 Camry, but that unit was just slightly deep.
This one is from a Prius. Not sure if it would fit, but it'll give you some ideas....