Huh. The specs look correct. Right height and volume is close enough ( 13 vs 14 ou, but perhaps I should not fill it all the way to the top? ). I thought this model all but disappeared particularly when I had walked into the now defunct BBB and found an entirely different glass (taller, different balance/overall shape) labelled as 'grand cru riesling' but perhaps it was a misidentified Veritas(*) version.
I could not find the glass on Riedel's website a couple of years ago either, but this confirms existence:
https://www.riedel.com/en-us/shop/vinum/riesling-grand-cru-zinfandel-641600015
(*)Re Veritas collection, the Bordeaux version is taller than the Vinum but equally functional while a touch more elegant. I've compared them side by side. Incidentally, when it comes to Bordeaux I have tried all sorts of stemware but have always stayed with Riedel. I suppose drinking as much Bordeaux for as long as I have has pros and cons, once you pile up so many reference points with the same glass.