What do you drive? I never paid much attention to them, but both my tractors have one adjustable on the right side. I adjusted both one time - just to make the axis of the 3PH pins level. You shouldn't have a hard time finding them.
If you don't mind me asking, why do you need two? Seems like there should be a pretty good range of tilt in both directions by lengthening/shortening the one side................chim