Ah, OK. Thanks, Thomas! I can see that thanks to deskthority wiki. It seems they were
supposed to use an E in those models, but didn't always bother to do so. If I google it, though, most of the results happen to be the Erase-Eaze version. Of course, looking at eBay, there are currently none listed, and the majority of NMB keyboards listed are of the dome with slider variety. I'll keep looking! Fond memories because clicky space invaders were the switch with which I learned not to hunt and peck.

...
SO much better than MX blue and clones thereof!