Black "paint" on the pillars
 

I think I have already seen a thread about these, but can't find it.

What is the black material on the pillars (outside)?

It looks like paint, but isn't.

What can be done if it gets scratched?

Actually I think it is paint, although it's not the high gloss finish you have with the rest of the vehicle. I wax the pillars along with the black roof rack on my 08 ES to provide some protection for them.

As far as fixing scratches, I think you could find a black spray paint in a low gloss or flat finish that would pretty much match. As long as the surface was properly prepared before spraying it should come out looking like factory original.

Is a plastic cover, under it you get the same body color. . .

yup
 

like the material used for pinstriping or company logo decals. It's not paint but more like a self-adhesive plastic film. Like this, but wider:

http://www.shop3m.com/75346289715.ht...-Striping-Tape

any auto detailing place should be able to get it and replace it. Certainly a body shop.