If you only go through a hundred or so patches a year, fine. if you go through several hundred a year, you may want to see about a bulk order. Part of the problem, is that if you look, you can sometimes buy MILSURP or other bulk cleaning patches for about the same price as buying material and cutting it yourself.
Most cotton flannel is ok for cleaning. Every once in a while, Numrich (Gun Parts) or one of the others offers a deal on cleaning patches, I bought two large cases of mil surp 30 cal cotton flannel cleaning patches about 20 years ago They are 2 in squares. Im down to the last several hundred. I think there were 5,000 in a case. Check around with some of the web sites, like Gun Parts, etc.