If the OE bars are exactly the same - and the S40 & V50 & C30 is interchangeable - then you may have some options.
I know from a very good authority ( ;) ), Hayman Reese have a
S40 towbar and a
V50 towbar.
But none specified for the C30.
Possibly, the S40 or V50 may fit the C30.
Failing that, you'll need to speak with a reputable fitter who can look into it - OR - make a bar for you.
Cosmopolitan Towbars in Mascot fits and makes their own.