If you have a P60 compatible Surefire light, you should be able to get a IR LED drop-in for it. I know batteryjunction and Dealextreme both have one (DX will be much slower and quality could be hit or miss).
There are several surefire models that come stock with IR emitters.
M1, kroma milspec, vampire immediately come to mind. You can also get filters for otherP,C,M lights which will allow you to temporarily have IR when needed.
Be wary of DealExtreme, it is trully hit and miss in terms of the quality. Two out of three I ordered was broken after just a short while, the third is running fine but if I had to start all over, I would have went with battery junction or even someone else.
Couple of pictures and short videos of Surefire V2 Vampire. Taken with Sony camera with removed IR filter.
Garage is pitch black at the time of taking shots and videos.