I know the Miracle Diamond has less prints than the Myrsterious Pearl. How many Diamond were roughly printed?
Supposedly around between 30-90 copies were made.
I always heard 27 as the magic number. I was never certain about that number.
Oh, Bulbapedia… 
A few sources claim that Battle Road Summer 2007/2008 had 27 tournaments. In retrospect, the aforementioned website lists ten (10) active tournaments. Regardless, depending on the distribution method (i.e. one winner per region vs. top three ranking players per region vs. top three ranking players per age division), the spectrum would be 27 – 30 – 90 copies, respectively. Bulbapedia declares the highest number of winners simply because they performed their calculations as though every age division won 1st, 2nd, and 3rd place. This means that instead of one winner per age division, there would be three:
3 Winners x 3 Age Divisions x 10 Tournaments = 90
I do not believe they assigned this many. Again, who knows? It depends on how they distributed the prizes.
It is interesting to note that they list the Mysterious Pearl as being even less in number than the Miracle Diamond.
C’mon, Bulbapedia.
Yes I don’t always trust bulbapedia. I always heard 27-40.