It really varies from organization to organization and based on role (full time or part time) and obviously experience. Someone doing it full time typically will be anywhere from $40k-$70k. Some make more if they've been around longer or have a different relationship with the organization and then obviously if you take on any kind of management role like Head Scout or Director of Scouting that salary shoots up more into the six figures.
Someone working part-time will be more in the $20K range. But again, this is just a general guideline. Organizations are all different, have more or lesser budgets, different arrangements, etc.