Mud flaps/Spats?

[MX-5 Lazza]

I have a facelift 2011 C220 CDI BE but it doesn't come with mud flaps. My guess is that this is for aerodynamic reasons to improve the efficiency. It does however mean that the sides behind the wheel is constantly covered in mud this time of year.
Is anything available? I've looked on the Merc website for accessories but can't see anything there. I've also looked at aftermarket but only seen universal flaps that require drilling which I don't really want to do.
Is anything available or am I just going to have to wash it more regularly?