I know that
G80-11900 and possibly also the Cherry G80-11800 have been manufactured with doubleshot white-on-black keycaps, and those two keyboards have a 2u right Shift.
I know I have had one from such a set, but I think I must have sold it a long time ago.
A 1u WoB Shift could be available from an Ortho kit in a more recent group buy.