Not sure what one runs from the dealer, but here is an online place that you might be able to get a used factory sub:

Car-Part.com--Used Auto Parts Market

If you want new factory subs, the part numbers are as follows:

Left - 05102804AA
Right - 05102806AA

Call the dealer to get the latest prices.

Also, on the forum here, MrMopar parts out Crossfires and he might have some used subs that he can get to you. Look him up and send him a PM.

RL