That's a very helpful link indeed! I've got a couple of these massive cylinder vases, I believe them to be fairly early.
Shape catalogues were not produced until '82, so this shape and size do not feature in the catalogues reproduced in Mark's book. BUT.....
One of mine has this wide black label on it's base - (mostly worn away).
My interest in these very large cylinders is that it is fairly obvious that the technique of using silver foil is clearly still being perfected - some of it has started to react with the molten metal, producing a slightly iridescent yellowy bluey sheen, colouring the glass rather than sitting on it.
This would make it a fairly early, early piece, and it's size indicates an experienced glassmaker making it.
Both the flame mark and this label indicate early - but the flame mark at least can't get lost.