Best Places to Buy Sake in Tokyo

I will be in Tokyo for a limited period so I am looking for one or two places which have reasonable prices and carry hard to get sake like Juyondai, Kuheiji, Aramasa, and the like. I won't have the time to research prices and go to many shops and also looking for a shop that sells to Foreigners who are taking the sake back to there countries.

How do depato compare with specialty sake stores on Availability/Prices?

Are availability and prices at online sellers (in Japan for Japan delivery) comparable to brick and mortar stores? Which online stores are best for Sake?

Thank you.

Here are some recommended sake specialty stores in Tokyo: http://bento.com/sakestor.html

looking for a shop that sells to Foreigners

None of the shops discriminate based on nationality, but if you're looking for someplace where they have English-speaking staff, Hasegawa Saketen has a branch inside the Palace Hotel, so I imagine that they would probably speak English. Kimijimaya in Ginza might have someone, but I'm not sure.

How do depato compare with specialty sake stores on Availability/Prices?

Some department stores have well-stocked sake specialty shops, some have a few bottles on a shelf; it depends on the store. Isetan in Shinjuku probably has the best sake selection that I've seen.

carry hard to get sake like Juyondai, Kuheiji, Aramasa, and the like.

The only shops I've seen that carry Juyondai tend to reserve it for their regular customers. Maybe try the Juyondai bar in Kyobashi?

I'm really not sure what the crossover is between sake shops with hard-to-get sake and sake shops with English-speaking staff. Again, maybe Isetan in Shinjuku would be a good bet.