Bento at each train station

I will have a trip to Tokyo and wanna know any bento style at each train station available in supermarket.
In order to try at one places, no need to go various places.

Thank in advance

I have heard of one store (‰w•Ù‰® ‹É) inside inside the paid fare area of Tokyo Station that seems to sell various ekiben from across Japan, but I cannot confirm that it still exists or its location. I get the feeling that it was replaced with a different store in a recent "renewal".

I also remember seeing and using a similar store at Ueno Station (also inside the paid fare area) a while ago, but that station also just got "renewed" and I am not sure whether the shop fell victim to it.

Various supermarkets and department stores periodically have, furthermore, temporary ekiben fairs, but it will be difficult for a tourist to hit such a fair.

Gransta at B1 level of Tokyo Station has many ekiben shops all in the same area. It's within the ticket gates (paid area.)

If you're outside of ticket gates, go to Daimaru Department store. They have tons of bento too.

Wow thank you. for all answers.
any other suggestion ?