Well, I figure since the moon is "International Territory", it would be like International Waters --- if you find a ship/boat/island that is completely uninhabited, then it's yours for the taking (salvage hunters, etc.)
I think NASA would be more concerned with the HOW I got to the moon rather than the silicone disc, however.
The slingshot idea, however... genius. I could build that for less than a million, I would guess.
And then, yes, sell the chip for --- one million dollars!!!
(Uh, Dr. Evil - - - )
20 million, yes, that's right.