Here's a link to a reputable retailer for the OEM part. It's interesting that it states it is compatible with the M340i so it looks like M340i buyers can replace their ugly grilles with this one.
https://www.bimmerworld.com/Body-Aer...QaAkchEALw_wcB
Note that you have to match up your parking assistant options as this particular one doesn't have holes for the cameras.