[HaloNHorns2002]

I couldn't find anything aftermarket so I made one! It's a used pillion seat base, a 12x12 piece of aluminum diamond plate and some hardware. All in it was probably $40 including the seat from eBay. It's a little ghetto but oh well LOL at least I can carry stuff more securely now!

 

[Gromit]

You can get rear racks. It fits on in place of the grab handles.

 

[HaloNHorns2002]

I looked at those, but they were bigger than I needed. Thanks though!