Looking for motor head casting part

Buy offer Details

Hello, I have been 3D printing these parts for a while but I am ready to upgrade to something heavier duty. I was thinking of either injection molded plastic or possibly having them made out of aluminum if the price was right but I don't know the best process for that and would need advice. I've attached a 3d model of what I'm talking about. I would be looking to get a sample to check fit and quality and then, order 100 or so of them depending on prices. The dimensions for the attached Stl. file are millimeters, would just want a bare aluminum finish. Looking forward to hearing what you think