You need to find out the RMS power output of the stock amp. Additionally the Ohms that the amp is rated for.
Then, you can match a sub to those stats.
One of the Skar subs should probably work. Make sure that if you buy dual voice coil, you are able to wire the two coils to get the Ohms that match the amp. For example, if your amp is 4 Ohm, do not buy a 4 Ohm dual voice coil sub. a 4 ohm DVC sub can be wired in 2 ways: series (8 Ohms), or paralell (2 Ohm).
Then, you can match a sub to those stats.
One of the Skar subs should probably work. Make sure that if you buy dual voice coil, you are able to wire the two coils to get the Ohms that match the amp. For example, if your amp is 4 Ohm, do not buy a 4 Ohm dual voice coil sub. a 4 ohm DVC sub can be wired in 2 ways: series (8 Ohms), or paralell (2 Ohm).