Korean stores have green and black loose teas. I drink a lot of tea at home and at work and my standby is the Chinese Royal King jasmine tea in square orange aluminum cans.
I am as wary of Chinese products as the next person, but have been drinking this tea for years, and it is very consistent and good quality for the price. I brew it twice and second infusion is decent, too.
I've also bought Japanese sencha and Chinese gunpowder teas there.