Alright. The colours are essentially dark green or dark brown. I would recommend dark brown for driving. I'll look for prices right now.
The cheapest I can find, cheaper than eBay, is $123.

Polarized goes for around $150-$160. They don't have gunmetal + black in anything but polarized, but I say these are pretty good choices.
http://www.framesdirect.com/Persol-2...-mdn-lani.html