FYI, I wouldn't have Jon rebuild the supercharger as they have quality control issues. Jon is very nice and I in fact had him rebuild a mp62 for me several years ago but never ran it before selling. The new owner had a issue after a year or so of running it, unsure of what happened beyond it no longer had oil in it when Jon got it back.
I'd recommend The High Speed Lab,
http://www.thehighspeedlab.com/index.html , many miata owners have used them and have seen zero complaints.