Ran into somewhat of the same problem
Went over to Auto Zone
They had a 12 point metric interal wrench set
Thats whats on the package
made by OEM parts
I needed it to take off the cap screw on the rearend rubber mounbt on my 560s .
I think its the same , when I first looked at it it had me thinking
count the points if there is 12 its it