Bumper Support bolt parted ways...

Last May I recently installed an M3 rep bumper on my car. I took this car to TN to drive the tail of the dragon, took it to the drag strip a few times over the summer, essentially put it through a good amount of stress. But the other night, simply rolling over a speed bump I hear a loud thud, and my drive side tire started rubbing. I pull over and look and the bumper is hanging off from the driver side. I'm very familiar with how the bumper attaches to the car, and I knew right away that the bolt fell out. I searched around the road nearby but to no avail. So my question is this, does anybody know what the thread pitch and diameters of this bolt are? I need to pick up a bolt that will at least fill that gap until I can order another OEM one, and I'm scared to drive the car without it in there.


Thanks guys!