Are you living in the UK? If so try to get in otuch with a company called Headset Services who will answer all your questions.
I use a Sennheisser HMEC 25 KA which is excellent: I estimate that I am 20% less tired at the end of a day's flying. I fly a 737-300 and -500. I think that the KA indicates that the headset has dual jack plugs and it's own power supply. Some aeroplanes intercom fits have a built in power supply for ANC headsets.
If you are in the UK make sure you send your receipt for your headset to the Inland Revenue with a polite letter explaining that it is safety equipment not provided by your airline. They will credit the purchase price to your tax code