Hare Canvas and Tarp in Markle Ind, right on 224 made mine. The are a biker owned company and he makes alot for HD lids. I got the idea from Big Mike. His friend Ron? made him a set. Mine velcro inside the lid. The rear velcro flap would not work the way our bags are desinged so I just folded up the flap between the lid and cover. I did take the bag gasket off to get a good seal. No problem with rain or stuff. I did get a tiny bit of sand in them 3 yrs ago from South Dakota after a storm, but I expected that. Sand was so deep on the roads the snow plows had to remove it.

I could have gone pure leather but opted for the leather/vynal with felt backing. $100 for the pair.
You could try some HD lid covers or I think RideTech? has some to, even with the stuff sak mounted on it.