I have found that plastic zippers are spendy. What I have been doing is going to the Dollar store. There I purchase the large mesh laundry bags--there are 3 in a package and the zippers are 11 inches long. I take out the zippers and use them for any project that requires a zipper 11 inches or under, as they can be cut off or sewn over. If I want a different color I color them with a Permanent ink Sharpie.
I have also cut off the top of the bags hemmed them attached one close to my machines to use for scraps and or thread. The bags can be taken apart then sewn together to make larger sizes of mesh fabric for ones use. Hugs.