How to restore my manga?

I have some Gantz manga that I would like to restore. I used isopropyl alcohol to remove a sticker, which then removed a matte coating that I did not know was on there.
I am thinking of using an acrylic based varnish spray to restore it...
Does anyone have a better option or way to go about this? It needs to be the right kind of matte coating as well. I live in the Netherlands so there are some American products that I cannot buy.