Purchasing new alternator

I am going to buy a new alternator for my 1991 accord lx but I need some help on choosing one. I have a 400 watt mtx amp powering my stereo and when I have all the electrical componets running, the volts on the battery drops to 12.3v while ideling. without everything loaded, the battery is at 14v+. I can get a Load Boss alternator (150 amps) for about $60 new and install it myself, but I was wondering if I would have to upgrade any of the power leads running to and from the alternator because its a high output alt. If I do have to upgrade all of the wiring, I would rather get an Oem alt. with low mileage. Whats your opinion? Is it worth it going with a high output alt. or going with a stock Oem alt. based on my power needs? Thanks for your time