Hm. I don't update data from the official site on-demand, just in batches every few days. I know what *has* been visible, because it has a picture or name; but even those are not necessarily available at any given time. I also run scrapes for series of part numbers on spec, just to see if pictures or names will show up. An example of the latter is
30 00 6693 - I wrote a script to ask the site for data on a list of part numbers I don't have yet, and this one showed up with a picture. It's not actually available to order, though. Also, the Ersatzteilefinden functionality is a javascript pop-up, so I can't even link straight to that for any number.
HOWEVER, this page has an ordinary URL:
Fresstrog II and for *available parts*, (not the klicky listed above), replacing the number in the URL with another part number brings up a similar page. I might be able to make use of that - even just to make the link without checking on availability, to let the user click through and look for themselves.