I was there today.
The man who runs it was very helpful.
He says at the moment the export of many food stuffs from India is banned due to domestic shortage. You can buy ingredients such as asafoetida that you can't buy in Okachimachi.
Highly recommended :)

This shop run by a young Japanese is an excellent place to find Indian foods. He speaks Hindi and English which is good for Indians living near Higashi Ojima. He possess a good knowledge about our country and respect India and Indians