I remember this coming up occasionally on the forum and was always met with "good luck finding them", but i've stumbled across this website today https://www.classiqueautowerks.net/fm-polo86c
Looks pretty reasonable if you're in to that thing.
The link you posted didn't work.
This one might be better.
https://www.classiqueautowerks.net/product-page/vw-polo-86-berg-cup-arch-extensions