Where to buy UK to JP plug adaptors?

Just moved to Japan, foolishly didn't bring enough adaptors for our British electrical stuff. Anywhere in Tokyo sell these? Would Don Quijote or somewhere like that be a good bet? Thanks!

-Any big electronics store such as Yodobashi Camera, Sofmap, Bic Camera, Yamada Denki (Labi).
-Daiso (100 yen store) sometimes has them, depends on the branch.

Just show the store employee a U.K. flag and say adapter.

Donki and 100 Yen shops don't sell those.
You can easily find A(Japan)��BF(UK except Scotland) adapter but BF��A adapter is difficult to find at local stores.
You need to visit large electrical stores such as Yodobashi, Bic Camera to buy it.
http://www.yodobashi.com/%E3%83%A4%E3%82%B6%E3%83%AF-Yazawa-HPJP5-%E5%...

I'll answer my own question - for anyone that's after one... 650 Yen at Donki (Ikebukuro). Bargain! They had a couple of different ones.