I was planning on getting a spare pair of prescription sunglasses. With the limited local selection, I eyed some pairs of Ray Bans, but they'd have to send them to the US to have prescription polycarbonate lenses done (unless I want cheaper plastic lenses with anti-glare coating). The cost adds up to about $200. Might it be cheaper to have the prescription lenses done while I'm in the US, with the wider selection there? I was told it would end up considerably more expensive.