This may or may not be helpful given it's quite a different style of bag and significantly larger. But I do have a Lowepro Dryzone 200 (essentially a thick dry bag with a backpack built around it). It's been used on one overseas trip kayaking along rivers in Belize. Just in case you were wondering - it floats
I'd be willing to let this one go if you think it fits the bill, but it was a very pricey bag. Not looking to get a lot for it, but I wouldn't want to give it away either being that it's quite unique and probably hard to come by now.