Home enthusiasts discuss their Foundry & Casting work.
If you are so inclined to invest in some sand and binder and core paste you could ram the mold and make the cores. You could paste the entire assembly together leaving only the cope to be closed. Take it to the iron foundry and simply ask them to cut the gates and risers and close the mold and pour it. Most foundry so are more than willing to simply pour the mold and charge for metal and minimal labor. Of course you need to take whatever they pour. If you are not willing to accept whatever they pour then it may be best to fabricate your parts.