Just a thought...if you've got the right part number, might be worth ordering from VW Classics in Germany directly. They're very helpful and you might avoid VWH's inevitable mark up. It's amazing what VW themselves have still got out the back in their shed (NOS blue heater levers, as an example, although that was a few years ago).
I didn't realise that either! it doesn't show up unless you do a part number search in the VWclassic section.
So we can get the worm, seals aren't a problem to get, that just leaves the bearings, i had a search on here and cant find out much, it was suggested "Fritt" had sourced some but ive searched his posts under "steering box" and cant find nowt, think i might take them into the local bearing shop when i get them out unless anyone has any sizes / numbers?