I know I'm about a 2 years too late, but if anyone is still looking for a place to alter denim I know an awesome spot! Studio Kim on King Street West does great repair jobs and alterations.
My wife recommends them...
A friend of mine, Zak, absolutly loves his tailor in Toronto. I'm not sure about the price but it might be worth a call. Zak recommends him here... http://www.gigpark.com/recommendations/30400306
Hope this helps!