A black zip tie works fine as a "clamp".
FWIW, the aftermarket gaiters I got for my bike lasted over ten years while I had it and are still on the bike, as far as I know. I forget who was the vendor. I treated them with Armor-All a couple times per year, which had the extra benefit of cleaning them when I wiped them off.
I also was able to keep the bike mostly out of the sun, except when I was riding it, which I believe helps a lot. I was fortunate to have a garage at home and a parking garage at work.
FWIW, the aftermarket gaiters I got for my bike lasted over ten years while I had it and are still on the bike, as far as I know. I forget who was the vendor. I treated them with Armor-All a couple times per year, which had the extra benefit of cleaning them when I wiped them off.
I also was able to keep the bike mostly out of the sun, except when I was riding it, which I believe helps a lot. I was fortunate to have a garage at home and a parking garage at work.