Re. How many CMP's still exist? How many of each type? - the jury is still out on that one. Keith Webb compiled a list, based on Peter Ford’s CMP-INFOEX. The people behind the UK based Canadian Register tried to do the same. All these efforts have ground to a halt.
Read some threads on this subject here:
Peter Ford's CMP INFOEX ??
Some CMP serials updates to the CMP database
The Canadian Register & CMP Owners club
CMPs - where are they now?
A few years ago it was tried to do the same for Dutch CMPs, there were easily 100+ back then, but only relatively few on the road:
Dutch CMPs
As the cost of restoring and operating these quirky vehicles continues to rise, I fear for the future of CMPs. May as well enjoy them as long as the fun lasts!