Missing Locking Wheel Nut :-(

[mac1986]

hi, seem to have misplaced the locking wheel nut key for my 2008 A6...

was going to break the nut but don't fancy spending 3 hours doing it for one wheel!!!

so I had a quick look online and noticed that keys are available on eBay. 

now I have no idea if the locking wheel nuts I have are genuine audi one but looks like key 820 is a pretty good fit...was hoping one of the experts on here could advise