Ok, found this old guy. Depth White. MX, early example. Sorry for poor pic quality; will take a couple of beauty shots in the daylight sometime soon.
With OG cherry WOB
Has lower profile than modern CC skulls
Old-style shallow FXE
On a piece of bright white copy paper
I know it's hard to tell the difference unless side by side with other clacks. Let me know if you want pics with other reference objects and I will try to oblige.