First of all I have to say that I would advise you to be "VERY" careful as a slight mistake in the power supply arrangements could render the camcorder useless due to the cost of spares, which if added up grossly exceeds the cost of the complete camcorder.
However in saying that a regulated and "STABILISED" power supply of the transistor variety giving an "ABSOLUTE" output of 12 volts at about 1.5 / 2 amps would work OK provided that two 3 amp rated diodes (1N5001 range) were put in "SERIES" with the output as they would kill about 1 volt from it which should be fine, just make sure that the round power plug has the centre pin as the +.
Hope info may be of assistance
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