Aye. A short fat object that I could fit in my eBay rivet tool would do the job. Just enough to splay the soft rivets would work...will see what they have at work. I think the standard rivet tool fitted inside the concave bit of the rivet so did not have much effect. Might even have something in the garage...
I have done more than 50 miles on motorcycles over the years and never had one come off or undone.