I have to record a choir this weekend and will be recording with a PZM microphone. Is anybody aware of companies that sell panels that attached to a mic or light stand that I can mount my PZM to? Obviously that plate on the PZM is too small by itself and I will need to extend the surface to which the microphone is mounted.
If you have to attach a panel, then PZM is not the proper choice of microphone. PZM is good if the proper place for the microphone is right up against a reflective surface (like inside a piano case or in a tiny room).
But using PZM for other kinds of things (where they must be attached to large pieces of plexiglas (perspex) was a fad from several decades ago, but most of us found that it was a gimmic that wasn't worth the trouble.
Why don't you just bring all the mics you have and try them out during rehearsal. Move them around and listen. That's the best way to find the best mic you have for the job. A good PZM placed in the right spot just might sound the best.