where i can buy near sighted RX eyeglasses for my uncle Lee?

[eyewear]

normally, the older people has near-sighted prescription, and then my uncle Lee can not read newspaper clearly as before. So yesterday he together with me went to a nearby eye care center to buy him a pair of near-sighted eyeglasses. Now with the help of the eyeglasses, he can clearly read the newspaper. But now, i want to buy one pair online, where i can buy it, thanks.