hi, y'all
I ended up buying a cheap second-hand (yet still in "like-new" condition) magnetic tank bag (that also has straps) off from eBay: it's a German (white label?) brand called "Hanson"
it's very neat, cost me a fraction of what a new one would cost, almost smells like new, very rugged/strong quality, still has all the tags and User manual, has more pockets and zips that I ever imagined or ever will need, transforms into a backpack, transforms into 4 individual pieces, its magnets are super-strong even with heavy groceries on the top "shelf"... and after all I really can still see the dashboard even in its highest setup :-)
I'm very happy with it and will keep it as long as I can even after the FJ is gone one day... as I can still use it in other bikes
here's a rushed picture I took:

regards