Double Copy on PGP hand

I had a double copy hand on Saturday playing Pai Gow Poker. I was wondering if anyone could tell me how rare that is. Now it was not a card for card copy. We both had K8 up top and on the bottom I had a natural A,2,3,4,5 unsuited and the dealer had A,2,3,Joker, 5 unsuited for a double copy. What are the percentages of that happenning?