(Edited for being didn't-read-it-properly nonsense)
Those are not Alps switches. They're clones of some kind. It's obviously a Macintosh keyboard.
If the keyboard is from 1997, it may be a Xiang Min (XM) switch, as they're one of the very few companies that made green switches, and they have the four small tabs. (XM started making them in 1997, and in 1998 everyone went gaga over translucent plastic.) That said, I've never heard of an XM tactile switch – they only do linear and clicky these days. Could be some other clone.
What does it come out as on the RipOMeter?