I believe you are referring to the Replacement Strap # 11952STRAP for the CIPA Universal Towing Mirrors # 7070-2. Other than that there are no other replacement parts and you'd need to replace the entire mirror. If just one needs to be replaced you can use part # 7070 as the part you referenced is for 2 mirrors. view full answer...
We do offer the Replacement Hardware Kit # RHK which you can order to get the correct replacement hardware for the Curt # C13136, etrailer # e57AR, or Stealth Hitches # 391AUDQ509 receivers. These are the receivers we carry which fit your 2012 Audi Q5, so be sure to include the hitch number when ordering. I recommend contacting the customer service department your dad ordered the receiver from to see if they can send a replacement receiver with the hardware. view full answer...
For your 2010 Audi Q5 we have the 2 inch Curt hitch part # C13136 which is a confirmed fit and would work well for carrying a bike rack designed for a 2 inch hitch.
Curt recommends the use of their stabilizer strap part # 18050 when using their hitch to carry a non-supported load like a bike rack. I attached a review video for you to check for the strap as well. view full answer...