Scotch tape makes these packs of pre-cut pieces of tape slapped together in a pad like post-it notes for sealing rips in stuff like dogfood bags. They are the exact same size as the priority mail stickers. I use those for a clear coat. Idk where to buy them, I got lucky and scored about 30 packs in a dumpster at Walmart. Also if you can find a roll of clear self adhesive book covers those work well for larger stuff.