Givi is the best rack, forget putting a renter on its not strong enough to take a box
Details
Or, Givi do a Wingrack, it mount onto the lower part of the rear pegs, seem to remember reading somewhere you have to change the rear pegs to the later longer ones. Unsure, might be possible to make up a bracket
Heads up, wing rack on eBay
I have a complete givi rack set up (2nd hand) on a shelf in my workshop if anyone wants one