Where can I buy small bags of Sunshine Mix#4?

Can anyone tell me where in BC a person can purchase small bags of sunshine mix#4? I'm not talking the 3.8 cubic feet bag that weighs 65 pounds. I'm after a smaller bag that you can put into your rucksack and hike up onto cliffs sort of size. I saw them a few years ago online but I can't find any stores that seem to have them. Has the smaller bag been discontinued? I need a bunch of them but of a size that I can carry in my pack.

Thank you for your feedback. Have a good day.

My local garden center carries them. It's in Langley. PM me for details.