Good day!

first time asking something here;
I recently got 4 emax mt4008 motors but they miss the holding down plate to properly mount 15inch carbon props...
since i did not find any reasonable priced replacements (I live in switzerland and shipping is generally very expensive from overseas) I thought about fabricating them myself.

Now for the part where I need help, can some one who owns such parts share the exact dimensions? I have some friends that have access to milling machines and they should be able to reproduce such a simple part with no problems.
as far as i know the middle hole should be 3mm and the two outer holes (distance 12mm to each other) have a diameter of 3mm as well. but what is the thickness of the plate and the total dimension?