I haven't gone looking for it in about 2 years or so, but most Loblaw's used to carry Swedish "Good For You" which is an excellent rendition of müesli (never heard it called "birchermüesli" in Germany). There was always 3 varieties - one with just grains and then 2 others with grains and fruits. I toss a bag of the all-grain version into my mashtun once in a while so I can call my beer "Good For You Beer" :-)
I hope I'm not cheating by adding Bulk Barn as a go-to source for muesli. It is, but the store version looks unexciting, to say the least.
Buying the basic ingredients here and making it yourself is the way of all muesli for me, though.
It's busy enough to mean that the stuff's usually fairly fresh, and dried fruits -- even relative exotica -- aren't priced as rare treats like they can be when you find them on their lonesome, in "$5, but don't I look good to snack on while you're shopping?" formats.
I haven't bought ready-made since Marks & Spencers closed up shop here...
warby
I created this "Muesli" entry to hold the dry granola-type thing.