I'm not sure if mangoes are sold all over, but they are available in the NYC area. I find them at fruit & vegetable stands on the street and in greenmarkets, and at Whole Foods as well.
Mangoes were on sale this week, I found this smaller ones, the brand name is Champagne. Most mangoes are larger than these, but these smaller ones have the benefit of not having as much fiberous material near the seed. On larger mangoes, the flesh closest to the seed can be kinda stringy. With these smaller mangoes, after you slice off the flesh, you can nibble on the seed, you can't really do that with larger mangoes, the fibers get stuck in your teeth.
Mangoes are also available sliced and prepared on the street. Prepared mango transcends a single ethnic group. I find these for sale on street corners in several neighborhoods. The mango is usually sliced, and placed in a zipper type sandwich bag. You can then have your choice of seasonings added. Hot sauce, salt, pepper, or lemon juice.
And mangoes are healthy. They are high in Vitamin C and beta carotene, plus they taste great. So go buy those mangoes in the store.