Finally I got the facts!

They were done for a friend of a worker at Innova and only 2 were stamped with this stamp.
Here is a stament from the person who got them.

"The kangaroo stamp has been used on lots of discs in the past and currently but only ever on 2 of the rocs.

I have a friend that worked for Innova. He had 2 blank orange / red rocs under his desk for a year or two. I finally did a big enough favor for him to stamp them for me. He would not give them to me blank. He stamped these 2 discs and that was it."

I now have pictures up of both of them.

These are beyond rare, with only 2 made, they are the most valuable Champion Roc... by far.

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