I've got some patches that I cut from a linen table cloth. They read .016 with a compressed micrometer. My WalMart pillow tick measures .018 with the same compression, so the linen is a tad thinner. It's cut into 1 & 3/8" squares for my .54s & .58, so you would have to trim them a little.

If you want to try them, shoot me your mailing address in a PM.