Many people use skateboard or roller blade bearings as a cheap replacement/Upgrade
www.3si.org

$2 dollar shifter bushings
$2 dollar shifter bushings w/ pictures guess what...you can use rollerblade bearing in the shifter cables...they are a perfect fit with zero movement...enjoy...a cheap mod with great results, who needs 25 dollar ones :) pictures of the mod are down the page a few posts :)