need help on finding alt pulley

need help on finding a alt pulley and it needs to smaller than 2'' inches i have a 81 bagged k5 that has a 160 amp alt and it is killing battery because i need a smaller pulley so if yall know anything please let me know thanks

look at www.speedwaymotors.com They have alot of aftermarket engine accessories, and I'm sure I saw one in their catalog for streetrods the other night.

thanks bro