The top box is a Honda item, but not available in the US yet. YOu can get all of this through webike.net. I have used them, and other than expensive shipping, they are great. I think the Top Box and Honda Racks will almost get you to FREE SHIPPING if it does not get you there already.
I am in no way affiliated with Webbike, but they are an incredible source of custom parts for our bikes. Remember, the CB1100 was availble since 2010 in Japan and Australia, so the aftermarket has been around there for a while now.
Gersh