I never bought swimming goggle from walmart since i am not swim. I just search at walmart and find that their prices are different because they provide various type of swimming goggles. the cheapest one i find just need $7.99 and the higher priced swimming goggles priced at $26.94. So, i can't give you a sure answer. If you need other detailed information, you can visit their websites or contact their services.
Usually the swimming goggles are divided into two kinds, the common one and the one with prescription which is especially for the short sighted men. And the latter one will be more expensive than the formal one. At walmart, the swimming goggles are at average priced at $12. You can base on your needs among the material, style, color and so on to choose your favorite one.