My favorite brand is Streamlight. If you look at their website, I'm sure they'll have one to fit your needs. Some of them can be a bit pricey, but I've found them to be worth it.

Another thought, if you already have the flashlights, maybe a good (and less expensive) option is to retrofit your light with an LED kit/bulb.

Assuming you have a Maglite, you can upgrade to LED for around $20 +/-.