I buy them from my local bait shop that gets them from here https://www.canadiannightcrawlers.com/shop/

I have been feeding those for months, they are dye/pesticide free, long and FAT. Very good company, come packed with dirt and container is ready to be refrigerated and you live in Canada so shipping should not be a problem. When my frogs are full grown adults, I will probably just buy them straight from the website since the will eat enough to make up for the large order.