I've never seen them separately, although I've not checked ETKA for this one.
Neither have I, which is why I'm checking it out - there's one on eBay but it's not cheap. I was thinking of trying the VW bodyshop to see if they had any from deployed air bags as it's only the badge I'm really after. Mine was scratched to buggery by the previous owner and it bugs me every time I get in the car.
I know a lot of parts on modern cars arent designed to be serviceable, but having to replace the entire airbag unit seems a little excessive. And they are very expensive (I'm not prepared to by an air-bag from eBay as my life literally depends on it)
If you have a moment to check it out, I'd be grateful.