D2 air deflector

My son's D2 has a air deflector type thing that is attached to a bracket at the rear of the sill cover, located in front of the rear wheel. Can someone point me in the right direction for the bracket and what it's called.
Sorry its a bit vague but below is the photo I am dealing with.
Might be the side step bracket.

It is the bracket for the side step. Those probably haven't been available on their own new for years but the part numbers are here:

Thanks James, looks like we will have to make something up.