I have just traded in my B6 A4 Avant and have the roof bars I used with it for sale on eBay, as they don't fit my new car:
Atera SIGNO Aluminium Aero Roof Bars 042 210 (110cm) for Roof Rails | eBay
I was always impressed with how easy these bars were to put on and off the car quickly and they are still in great condition as they were never left on the car when not being used.
The bars fit other cars, and those are listed in the auction.
Thanks for looking.