It depends entirely on your amp. If you plan on keeping that amp, it can only put out 1000w @ 2 ohms, which means 500w per sub. You'd still be underpowering each sub by 500w.
If you got two 4-ohm DVC subs, you could wire them to 1 ohm, and the amp would put out 1500w, or 750w per sub, which would be better.
If you're considering a different amp, well we'd need to know the specs of the amp. If you had an amp that could put out 2000w @ 2 ohms, then you could keep your existing sub, and get a second one just like it.