I wish I had first hand info for you. I have been wanting to go there for some time. You may check out the conditions at Le Massif ski area-it is somewhat south and west on the St. Lawrence. Also there is a hotel located right in Gaspe Prov. Park which I would think you could find thorugh a search and which I would think is an excellent source as they cater to back country skiers.
Love to read a post here afterwards about your trip and any advice.