There was one on dotCOM a few decades ago, but if I remember rightly, it was shut down when the more active posters started monitoring listings and warning of scams and fakes.
As I recall, these were not nuts with a vigilante mindset, they were just doing what is normal in philatelic circles, policing the site and warning off other members.
There is a current Stamp Board on dotCOM which is very concentrated on US stamps and may not be too useful for a seller who specializes in anything else.
Are you aware of the Canadian Stamp Dealers Association? There may also be clubs, shows or exhibitions in your area advertised in Canadian Stamp News.
In passing, might I suggest that you put the words "Hobby Stamps" at the end rather than the beginning of your titles?
Today's customer is likely to be Searching on a mobile, and apparently the first four words of your title show better on the phone Search than any of the others.
If the customer is Searching "hobby" or "stamps" the location of the words in the title is less important.
