I use my Roland Rhythm Coach practice pad with headphones. Works great for a metronome and also gives me something else to hit when using it with my kit.
It's also plenty portable enough so I can take it upstairs and use as a practice pad.
At some point I may add a KD-8 kick trigger to it so I can practice my footwork along with my hands.
I have the older RMP-2 model. The newer RMP-3 model is cheaper, but I don't think you can add anymore pads/triggers. The RMP-5 is more expensive, but allows you to add two more pads.
I don't know if this is what you need, but it works great for me.