This article provides a more detailed deck of cards for Saga Rules in Risus.

The Saga deck that comes with the Marvel Super Heroes Adventure Game is made up of 96 cards. Of these, 16 cards are used for the Doom suit (i.e. the GM Payback suit). In other words, 16.7% of the cards are of the GM Payback variety. In order to do something similar with regular playing cards, you could take 3 decks of cards, but only include 2 sets of Spades. This will get you to 18% of the deck being GM Payback. If you limit the Spades to only include one Ace and one ten (instead of two), you would be right at 16.7%. Close enough for this.

GM Payback Suit

Aces	1
2	1
3	2
4	2
5	2
6	2
7	2
8	2
9	1
10	1

However, if you use these breakdowns, the chance of getting a GM Payback card jumps to 21% (since we have only 4 suits to use instead of 5). If you change it so that there are only 1 of everything except for 5s and 6s in the GM Payback suit, then the odds remain about the same: 16.67%.

It might be more work this way, but then you get a better distribution of cards to use that might actually work better for play (assuming that TSR did their research when the originally developed Saga.