How many massage tools are sold in the USA, Canada, and UK ? what is the value of those sales?

In the process of writing a business plan I have tried to research the market for the massage tool I have patented. I know what my tool will do, and I have an overview of the available tools ( from $10 to $3000 ) and what they can and cannot accomplish - but when I am asked what is the number of tools sold / year I can find no way to find this online, and the Minneapolis public library was of no help.