Maybe, Both Heidegger and Alpina knows about these parts are redone and they really don't mind, even with the Alpina logo on it: That must should make you think. A German garage, like Richy Bauer has, would take a great risk to sell these parts if the logo is used in vain, a ticket for that is very high due to use the trademark Alpina. Maybe the castings were remade by the man who made them for Alpina in the first place. Maybe if you ask Anita @ Alpina she could sell you one of these.
It'll take an expert to see differences between the sets.
So, after there are remakes without the Alpina logo (they are also for sale on the web), you could have with, without logo and even Jenvey or Dbilas (last one i don't recommend): But we're talking about the A4 on this topic, so forget the last 2 mentioned.
Maybe, if you think of wanting one of these items, contact Richy and ask him about the sets: He is very helpfull, so opinions can go to facts.