The astute among you will recognise this as a new variant of the FD-0100, the Topre OEM product that would eventually be developed into the Realforce. Information is scarce, but we know the FD-0100 was offered to Japan's commercial and industrial sector, as sandy55 discovered a model with air travel reservation-specific keycaps many years ago. Sometime around early 2005 some stock of the base model FD-0100 appeared in Akihabara stores. My bet is this was Topre offloading their extra units as they prepared to move to the 108- rather than 106-key layout and do away with PS/2 in favour of USB.
It's evident that this thing's had a hard life
![Sad :(](./images/smilies/icon_e_sad.gif)
Cleaning the keycaps alone took over 4 hours of hand-scrubbing, but they're finally clean! For the time being I decided to put them on my 86U with some supplementary 108UH-ANLG caps. I absolutely love the overwhelming number of data-entry sublegends, blue front-printing and grey integrated numpad, which has seen so much use that it's super shiny, the texture is wearing off and some legends have begun to fade.