Hello Mary,
Those are standard metric screws M4 (4 millimeter diameter) with a lens-like Philips head (no countersunk): (Deutsche Industrienorm) DIN 7985, 4 mm x about 25-30 millimeters long.
The Mercedes parts number(s) is (are) as follows:
007985 004130 Screw
006797 004236 Toothed lock washer
The sad thing is if someone already used self-tapping screws (or woodscrews) before, mostly the screw thread in the door's aluminum frame is already (heavily) damaged and the correct screws with the regular metric thread will not hold nicely anymore ...
Good luck!
Achim