Room Enough For Two Atop the Cat Tree

I'm still really pleased with the Lotus cat tree I bought a few weeks ago. I was worried that the top of the tree wouldn't fit two cats, but it does, as long as they get along really well, like Arthur and Beowulf.

Sure, I'll still catch them wrestling up there from time to time and that does worry me abit, but, for the most part, they share.

Need Help Finding a Cat Ball

A few months ago, I was at a local PetSmart and bought a bag of three rubber balls (a blue, a green, and a pink) which became Arthur's favorite toys. These rubber balls are different from any others I've seen because they have these small rubber spines sticking out and they have bells inside which jingle as they roll.

These balls are superior to any others I've seen or bought because they roll slowly and are easy for cats to carry in their mouths.

I wish I had video of it, but Arthur will actually play fetch with the pink ball (his favorite color for some reason). If I throw the pink ball up on a chair or a couch, he'll grab it in his mouth and bring it back to me to throw again.

Unfortunately, these balls are starting to wear out and PetSmart doesn't have them anymore. I've been to dozens of pet stores and searched tirelessly online, but I haven't seen these balls anywhere. Does anyone know where I can find them?