I am having a little trouble envisioning which style of snap you are using. Normally the camper back use the "Dot" snap, with female on the fabric and male screwed into the fiberglass of the hull. The "Dot" are less likely to be damaged. The twist lock is most susceptable to damage. The lift the dot with stud into the hull sticks out a bit more. You can get any of those male with either a screw type base, or if the hole is already too big, a threaded machine screw. If the hole is loose for the screw, then use the machine screw type. I am not aware of a pop rivet type of fastener, although you probably could modify a cloth snap (male) to a pop rivet. I usually use the brass snaps, which are plated. They are less likely to rust. However if your boat is left in a salt water slip, then I would consider the SS.
I have to assume that you have no questions about setting the rivets. I have the tools which fit on a. special sent of vise grips, which I have had for over 40 years. I also have a set of manual punches and dies so I can set rivets when on a cruise, as part of my emergney repair kits. As far as pop rivets, I have multiple tools up to and including a hydraulic set. I have a set of cloth punches for cutting the holes. I also have the Sail Rite dies for the "lift the dot" and the turn button fasteners. IF you are just doing a very few, I used a flat plate on an electric soldering iron to burn the small slits, so they don't unravel.
To have stronger canvis sets, have the female side through folded over edge of the canvas, with some stiff material inside of the fold. I use 9 to 10 oz dacron sail cloth, but a small piece of vinyl such as the Weathertite fabric, with PVC vinyl over dacron scrim. (Like the
PVC inflatable dinghy is made of.) will work as well.
In the long run buying one of the backing and cutting blocks will be easist to use and on your punches. There is a plastic and a rubber side. Use the rubber side if there are tabs on the die, which are easily broken. Buying some decent but not the really expensive professional level tools now will make it easier to do canvas work for many years.
