Can you replace the lenses in Louis Vuitton sunglasses?

I have a pair of Ursula Strass LV sunglasses and I don't like the color of the lenses. I was wondering if anyone knows if I can just take them to an eyeglass shop and have RX lenses put in or if LV can put darker lenses in and about how much would it cost? The glasses were $585 so I really don't want to put that much more money into them.