agree, it does look to be Hermanova pre 1958 Pattern 18888 example - it's a shame that Pamela Wessendorf's pressglas.pavillon appears not to have an example - we would then have been able to show the image from Pamela's museum. However, if anyone has the Sklo Union (Marcus Newall) CD, then page 5 shows most of the items that were produced with this basic design of irregular ribbs - similar to the vase 18888.
Item 18729 from that page is similar in the sense that it shows a vase - albeit minus the circular foot arrangement - but with the zig-zag ribbed appearance with alternate ribs showing the frosting.
Nice piece by the way.