Here is a picture of mine with the dimentions. I am guessing it is indeed same, as the half centimetre difference is probably because i measured it inside the boot.
So i think I am gonna order it.
By the way: it seems that screws that are holding it in place (second picture) are 'audi-special' haven't seen them before. Any idea where i can find a screwdriver for these?
Thanks for the tip on the spare wheel size, mine is also 145/85 R18.