Sorry I just saw this thread.
I know it's too late for @Max, but at least for those who are visiting Tokyo in the future, in addition of all the shops already mentioned, people can go to Tokyo Station. On the lower floor (I think it's B1) there's a kind of mall with most the shops of the main brodcasting stations, like Fuji TV, NHK, NTV, Asahi, TV Tokyo and maybe others. There are some drama goodies there.
That being said, the shops are small and crowded, so there's probably nothing more than in the main shop of each station (just took a look at the Fuji TV shop in Odaiba, where there were more things than in Tokyo Station). The main interest is the fact that you've got several shops at the same place.
Plus goodies seem to be available only when the drama is airing or some months after (though I managed to find some Hero goodies too, in the Tokyo Sky Tree which was not that bad tbh). In fact, i'm wondering if there are lots of goodies for each drama. It seems ridiculous that in the main shop of the TV station, there is not everything available for a drama. This summer, Code Blue was airing, but they weren't lots of goodies for it in Odaiba, I was a little bit disappointed in fact.