Q: Soccer?

My dog loves to play soccer but she is small so I need a small soccer ball. I had one but it broke and now I can not find one that is small enough for her I think it is a fun game for both of us and good exersize too. Skitters is a rat terrier a normal sized one and she is on the large side but the soccer ball has to be soft but not too soft and I can't find one anywhere the old one was for a very small child.