@north,
You're right, my initial response was flippant. But my real reservations lie in these points:
The term "spirituality" has a religious connotation.
While it might be reasonable to overlook minor differences, it is unlikely to occur on a sufficiently broad scale to make this happen, and from a certain pov, thus impractical.
i don't really see an immediate incentive for establishing, or the costs of building and maintaining , these international institutions