Take YOUR alternator off and take it to an old-timey "Alternator/Starter/Generator Rebuild Shop". A week later you'll get YOUR alternator back. You want it to put out more amps? No problem!
As far as batteries, *I* like the (relatively) new "Glass Mat" technology. I put a top-of-the-line Sears Die Hard in mine 4 years ago; haven't even LOOKED at it since, so I GUESS it's still in there:
http://www.sears.com/shc/s/p_10153_1...31-107145614-2