Hi Clint,
That looks like the SW Motech AluRack (sp?) rack. The good news is that the center section holds the adapter so you can put almost any topbox you want on there. Just go to Twisted Throttle website and pick out what you want. I would pick out the top box first, then figure out what adapter to buy. I used the givi monolock adapter and a givi v46. I think Phil runs that rack with the a different top box.
I still have my givi v46 and it is still running strong and sporting my NT-owners.org sticker from the 2012 national rally.