I guess a balanced way to do it would be (I haven't looked at those rules, but judging from the explinations above)
base riot dicepool 8
consider BestCopper 5
and WorstCopper 3
First roll 3 dice (8-5), to determine result agaist BestCopper,
then roll 2 more (8-3=5, then -3 already rolled), combining with the 3 already rolled to find more pairs.
(I think this is elegant, but as stated haven't read those rules)