Chloe Esther CH0008S - Patricia Arquette - High Desert
We don't have confirmation that this is the correct brand and model but we are pretty sure that these are the Chloé Esther model.
The sunglasses have an oversized, octagon frame with a black or dark havana frame and gradient lenses.
Buy on Amazon ($189, best deal).
You can also find the Chloé CH0008S on eBay.
There are a few similar models with sligthly different frame shapes.
Salvatore Ferragamo also offers a nice pair of octagonal sunglasses, model nr SF1070S, find them on JomaShop for $60.
Another similar model is the Guess GF6152 (on Amazon for $28).
Throughout the same series, Patricia Arquette wears metal Ray-Ban Aviator sunglasses, read more here.
Reference: Chloé Esther CH0008S Havana 004