I purchased my "Bench Cookies" from Amazon.ca (noting that you are in Canada) - search Bench Pucks. They are thin sponge circles for adhering to hockey pucks. They make a great base for razor hones. I never looked for anything else once I found these.
This is what I use. It holds the vast majority of my JNats. Unless the ends have really wonky angles, it should grab it well enough to hold the stone. The 3 piece design works well dealing with irregular shaped bottoms, the middle piece can be slid wherever to adjust for any uneveness. Some guys like just rubber blocks. I like the added stability of slight pressure holding on the ends. If a favored stone of mine is really out of wack (shape wise), I will make a dai if its bigger than a small koppa.