Need new manifold.........asking for help please

When I bought my Duster it came with a 318. Someone had installed a Eldebrock 750 on the stock manifold. I am having no problen with the fuel system or its performance. "Charlotte" has stock exhaust manifolds but has duel exhaust all the out the back. Looking to change to an aluminum performance manifold and also the valve covers.

1) Which manifold would be recommended?
2) Who has the best prices for the manifold and also valve covers? Looking at putting the wrinkle black Mopar covers on.

As always ya'll are the best. Thanks for the help.