I have never seen this keyboard before with green ALPS, but I managed to find this one NOS for $75. This specific keyboard went under the moniker "Rayton," however it is clearly a Monterey K108 keyboard. It definitely looks like it, and the FCC ID on the back is the same as it is for all the other Monterey K108s.
I can't seem to dig up anything on the "Rayton" company, either. Very, very interesting stuff, though. I want to use it as my daily driver, but I kind of don't want to, also.
https://imgur.com/gallery/JZiTUvfDoes anyone here know about this keyboard or the brand "Rayton" at all?