Mirrored (Half-Silvered) Plastic?

I thought it would be cool and more true to the movie to have mirror lenses for a Clone Trooper costume instead of clear black plastic. I have a few questions/concerns:

Would you be able to reshape the plastic without screwing up the mirror coating?

Where would I be able to purchase some of this material?

Is there any substitute material I can look into?

 

You might check out PECH Optical. As an optical lab tech I used to send them lenses all the time to be coated. If you made the lenses out of smoked plastic, then sent them to PECH, they could coat them for you. Might be a bit pricey, but it is an option.