The Japanese version has only one Vigor Ball, which is the 2nd in the U.S. version located where you recruit Sheela (in the forest there). The U.S. version, however, has two, adding an additional vigor ball to the hidden forest. I'm not sure which method PAL/UK uses, but you can check by trying to gain access to the Special Stage. If you can get there by walking around the entire map, then it's like the U.S. and there should be two vigor balls. If instead the only way to access the Special Stage is on the bottom path by traversing some bushes hidden behind trees (it's not a straight path) and then walking up some invisible "stairs" above the tree line over the entrance and then back down again, then it's the Japanese version and there's only one Vigor Ball. Hopefully that made sense.