I think you can just put a capacitor on the power leads for the camera. That's a strategy most circuit boards use to regulate power to sensitive chips. I don't know what size you'd need - I'd imagine a rather large one... but this should accomplish what you want. If I am totally crazy (I'm an ME, not EE - anything is possible) and you can't use a capacitor, I am fairly confident there are voltage regulators available on Digikey.com .
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This isn't quite what I was talking about... but here is a voltage regulator on Digikey:
http://www.digikey.com/scripts/DkSea...449095&Site=US
Hope this helps!
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