Thanks! I had worked that out. Because I'm trying to scale a sprite, the only values I found for it are pixel based and not world unit based. So to convert the sprite pixel size to world unit size, I needed to know how much a world unit is worth in pixel which is not given anywhere. The solution is relatively simple, it's `height of the screen in px / orthographic scale`. That allowed me to scale the sprite and then work out the pxPerUnit difference between the sprite and the world to correct the ratio. Hope that made sense.
All of this to say, it's great to have the dimensions of the screen in world unit using the orthographic scale and the screen ratio, but knowing the current pxPerUnit for the camera is an information that the framework doesn't deliver and is necessary to build responsive games.