You might be able to get something cheap or even free from a carpet dealer:
Non Slip Rug Pad.jpg
A 2'X3' piece is about $10 on Amazon > rug pad grippy
Small pieces of this are great for hard to open jars. They also help hold work on the bench when sanding. A small piece is good for getting a grip on the work when using a shooting board. Great stuff.
For my water stones an automotive floor mat purchased at Target over a decade ago works fine.
jtk