From Dollarama it is $.99 for 48 bags. The manufacturer of the bags has a website http://www.epi-global.com/
discussing the technology of the biodegradability of the bags and plastic products. It is still unclear to me whether the bags are completely biodegradable or remain as plastic powder after decomposing. I lean more towards incomplete degradation, since it is still plastic being used.
To save bags I re-use them as long as the poop did not leave reside on the bag, luckily Leo's poop is pretty consistently firm, so I have gone almost a week on the same bag, I just stuff it in my back pocket lol.