That Japanese page said white Alps.
It's Alps, Jim, but not as we know it …
SPARC's sent me some photos of the switch. Short switchplate and slits, as you'd expect, but the upper shell is missing the numbers in the circles, and the Alps logo. It does have the numbering at the top right.
From what I can tell, the upper shell is identical to the ones used in the Simplified Alps Type III:
http://sandy55.fc2web.com/keyboard/focus2001.html (click "Fake Alps Blue Type-III" at the top then scroll down a bit)
This ties in with a theory that Simplified Alps Type III was created using rejected switch moulds that were thrown out — someone else picked them up and adapted them to fit clone parts. The DSI keyboard has real Alps switches using these incorrectly-moulded switch shells!
I was suspicious right from the start because the moulds didn't look right.