Interesting that the company usually happily deals with thousands of requests without ever asking people to go to the forums for more response, hence such greats as the clash and possibly winning a pass gifting league...could not write it. Anyway this is actually a golf idea, and you were obviously straight to the forums:)
Yes I would use a Nike L81 ball in yellow provided it cost not a cent more than the white one.
Ideally maybe make the yellow one a L82 with a 4 meter, and then they could perhaps charge 575. New meter would may be nicer for putting, IMO:)
GL with it and why they don't just do it if there are RL equivalents I am not sure