For the power outlet, I used one of these to cover the opening, because my car didn't have anything in the empty hole when I bought it.
https://apexfasteners.com/fasteners/ima ... e-Plug.jpg You can get them at the hardware store.
The black handle insert for the rear door, it's actually made of hard plastic. I remember mine because it fell out after being rear ended. I didn't see a part number for it but I'm sure a Gen1 owner can pull it out and find the part number for you.