This is one of a few spots you feel you are strolling a narrow street somewhere in Asia. Although the space is tiny, B1 of Ameyoko Center bldg in Ameyoko, Ueno offers a lot: from　live turtles to plantains.
If you are looking for Asian food, fish, meat, veg, this is the best place to start.

Ameyoko Center Bldg. B1
4-7-8 Ueno, Taitoku, Tokyo

B1 Aocyu Shoji Nozawaya青忠商事野沢屋
Chili Peppers, plantain, banana leaves, asian veg, meat, Indonesian spice mix such as Bumbu, Sambal

B1 Arai Shoten（有）新井商店
veg, canned& dried foods, fish, meat
B1 Hatsune 肉の初音
Lamb, Wild Boar, Pork Roast, duck
B1 Nodako Shokuhin 野田幸食品（株）
eel, frogs, turtles, crab meat

B1 Murachin Shokuzai むら珍食材
Thai Veg, Tempe
1F Hirata Shoten 平田商店