We of course have no way of knowing how many were made to begin with, and most of them are likely either sitting under some mountain, or at the bottom of the sea.
As far as how many are actually circulating... We really have no way of knowing that either. I'd guess less then a hundred, but for all we know their could be thousands of the things floating around the Land of Madmen.
As far as random questions we can't answer, I kind of wonder if there are any intact space stations left over from the AoL. The AoL had a habit of building things to last after all, and so long as such a thing managed to A. survive the war, and B. not have any male channelers on it... It should still just be sitting there. Hell, might even have an AI given that those seem to of been a thing in the AoL.
