My fan on the altornator has broke I have looked almost everywhere to find one and have found nothing. Can I use a aluminum fan for it or should I get the plastic one?

 

As long as the fan fits and it's for the alternator that's on the car, run with it. Thunder Racing has a billet aluminum fan for LT1 cars, but you might not be able to get your color as it's an MBA product and they're out of business.