I ordered mine when I bought my bike, the salesman said that it was 2 seperate pieces and had to be ordered seperately.
I think it's bull**** that they don't include a necessary part that is of no use when ordered by its self. The only use for it as far as I know is if you want to instal the sissybar.
So, yeah, talk to your dealer and have 'em order it for you. I haven't seen them anywhere available online (I haven't looked, but I haven't noticed them either)
Also, if you put a luggage rack on it, there are 2 different luggage racks, make sure to get the one that goes on the quick release sissy bar.