Generally speaking, for low volume (about a 1000 pieces)manufacturing of an alloy part (aluminum or stainless steel, I haven't decided yet) for which I can alter the design for the cheaper method, which is less expensive: forging or die casting?
Depending on the geometry you might consider Graphite permanent molding. For 1000 pcs per year you'll be hard pressed to find a source and if you do you'll be shocked at the costs involved for the tooling.