You might have to order from one of the Japanese online stores.
I also wanted a RF board with printed letters and uniform weight. Couldn't find it in the US and ended up getting the black one from EK.
I love it, my wife dislikes it whenever she uses my PC. She says if she has to type with one hand while talking on the phone it's annoying on a semi-blank keyboard, even for an excellent touch typist such as herself.