For the M3 it comes down to 2 options:
One listed above, 19x8.5 +20, 19x10+20
The other (I had this setup before)
19x9.5 +40 (Used 20mm spacer), 19x10 +20 (Used 5mm spacer)
The reason I went with the last setup is that I wanted a concave front wheel, the 9.5 will be more concave than the 8.5 even with higher offset.
There's a set but in black on the classifieds right now for very cheap.
Here's a quick pic of my old setup:
