I found a reverse camera for my Yaris sedan. It's listed for a Corolla but it looks like it should fit a Vios, Belta, or Yaris Sedan.
I'll poke around the Yaris factory repair manual to see if this will fit and will post of some pictures of where this snaps in on the truck trim piece.
Edit: Apparently the trunk trim is called the "LUGGAGE COMPARTMENT DOOR GARNISH" in the factory service manual. Just in case someone would like to go look that up.
