I replaced mine with a different brand. I went to:greatbigoutlet.com and ordered a WS 2010-15 wind cups. They worked perfect. Only thing is the hole that goes onto the shaft is smaller and you have to push it on and it holds really tight. Didn't even have to use the setscrew as it was really tight. Worked great for me.
If the magnet is the same for the 968 cups they should work also.