To save folks the search, these both sell ~$300 sunglasses.

They show action shots of people wearing them kayaking or at the beach but I'd be so worried about dropping them in the river or scratching the lenses with sand that I'd never take them those places. $300 is more than I paid for my kayak, LOL. Probably more expensive than entire sets of clothes I might wear while doing those activities, or at least right around the same price.