Wow.... explosion looks amazing but I don't have that kind of cash lol....
In that case I'll second Exodus's recommendation for Reed McClintock's version. It's on his Coin Ovations DVD. He uses Barber half dollars, which you might have to look around for and might cost a bit extra, but you'll still be well below Explosion's price tag.
You might also look at Volume 1 of Paul Harris's Art of Astonishment books. He has a matrix routine called Giant Killer Coin which ends with a jumbo coin production. You might be able to combine that with Silver and Aces from the same book, where four coins appear under four aces. It uses a homemade gaff that you might be able to add into your matrix routine - although honestly I've never tried this, so I don't know.
One other thought: you could also try doing David Roth's Free and Unlimited Coinage of Silver routine after a standard matrix effect. You can learn it for cheap on the Dinner Table Magic volume of L&L's World's Greatest Magic DVD series.
Hmmm, I might have to experiment with that last one myself . . .