even though i have to agree with the last post about new better than used, but there IS an inbetween. there are 2 choices, either find a gm wholesaler (kinda hard to find an HONEST one these days though, not my perferred choice) OR find an auto-electric shop. this is a shop that is dedicated to nothing but fixing and rebuilding automotive electrical stuff, especially alternators. going this route will not only make it cheaper *if you dont have them install it that is* but it will be completely rebuilt with quality parts as opposed to no-name brand reman. alternators which can bite the dust very easily especially it seems when the time is worst to happen. get it done by professionals with quality parts for cheaper, and it's still your stock alt.
"this has been a public service announcement from.. your mamma's bedroom"