Just ask for them at any
Canada Post outlet, and if they do not have them, ask them to order them in in their next order. No cost to you. I had my local P.O. order a bundle of them for me. They brought in 200 and gave me 1/2 to use. Just get them to order them by number as seen on sheet. Hand cancelled/ do not machine/ manual sort cover sheet. Order # 40-077-165 And if they dont know about them, ask them to check their manual.
After hand cancelling your cover wrap this around the item with an elastic. With the yellow slip the item would be hand sorted and serviced and not machine processed as normally done. This is a great way to have First Day, pictorial, and other cancels of covers serviced with the desired philatelic cancel, and not run through the machine obliterating your nice cancellation. Free to receive and use , but they still will not guarantee that the item may still be machine processed.
Jogill, they have been available for many years to help service collectors. Note the date on that slip 04/2010.