There are various brands and styles of sunglasses in super market. I can't tell which Walmart has retro sunglasses or not. I think you should go and check it your own. There are some other stores you could take into consideration, for example Lescrafters and specsaves. If you didn't find any sunglasses you like, I suggest you to surf on line. As technology develops, more and more e-business pops and booms. There are many popular eye wears on-line shops, which provides all kinds and brands and styles of eye wears. I think you should check on website. As to the styles of sunglasses, I think it depends on yourself. What pattern and color matching you most would be the best for you. Recommending some relative linkage just for your reference. Hope you enjoy shopping on line just like me do.
http://www.framesdirect.com/
http://www.warbyparker.com/
http://www.eyebuydirect.com/