JB you can try this. The Carrefour Mondial de l'accordeon in Montmagny, Quebec. Beginning of Sept. Several days of concerts and Festivities with many local accordion builders exhibiting their accordions. This is a very popular festival so book rooms far in advance. You should be able to get all the information you need to go on Bing or Google.
On a scale of 1 to 10 this festival and series of concerts is a 10.