Where to find replacement tail light plastic for project?
 

I'm planning on modifying my tail lights and have fun into a problem. The tail light lenses are heavily diffusing (see pic below). I'm looking for some plastic that I can fashion to replace the pieces.

I'm not sure what they're made out of, but whatever is interchangeable will work for me. However, my one stipulation is that it be DOT approved, or keep the tail lights legal. I'm not a big fan of illegally modifying my car when it comes to safety things that can screw me if I get in an accident.

Any leads would be great.

The pic is a ball point pen taken through the housing. The pic is a bit blurry but that really doesn't change the result much.

i`m looking for some kind of clear lenses but legal and DOT approved,state troppers in CT pain in the....if you get some info. let me know,thanks.