Indeed! Unfortunately, I had a terrible experience with this because the P. O. or dealership drilled out the snaps with a large drill to install the belt rail.
I went to a local upholsterer and bought ALUMINUM snaps and sourced aluminum rivets for fear of oxidation. They're the "standard" size snap and readily available.
Oddly... when you were posting this, I was on the phone with a local canvas shop asking if I could stop by and have them replace one snap that came off my NOS Tickford. Luckily, they are accommodating so I don't have to buy the installation tool!