-
Check out Bike Bag Dudes facebook page, he made a bar bag that fits in the space of a Jones H-bar...just turn it around so the tapered edge faces the wind. You could get him to do a little clever resizing to the width you need and it'll suspend perfectly off the aerobars, and be aero too!!
Edit to add: his garage top tube bag is one of the largest in the business too, if not the largest.
Any cool bar bags that are easy to access that will work nicely with aerobars fitted?