I had micro-balloons come with MAS epoxy in my kit from CLC, they work just fine. I don't know the manufacture. Call CLC or MAS.

Wasn't aware of any compatability p[roblem with micro balloons. They are glass bubbles, inert chemically, should have no effect on any epoxy. Back in the `70s and `80s when I owned a hobby shop I believe the "microballoons" were phenolic resin, also fairly inert. Now I use 3M Bubbles which are glass and can be purchased cheap in bulk.

The ones CLC sells are phenolic. Both glass and phenolic are compatible with epoxy. The most obvious difference is the color.