What kind of price would one intake cost to get copied
You can't just copy a casting. For one thing, the castings shrink after they are poured, so if you were trying to copy a simple casting like a valve cover by just using it to form the sand on both sides, the casting would come out too small; the aluminum shrinks as it cools.
If you were determined to do it, you would need a 3D model of the intake. For about $5K you could get the intake X-ray scanned and get a model with all the correct aluminum thicknesses, water jacket locations, etc. Then you would have to size it up by some percentage to account for the aluminum shrinkage. Then you would have to give it to a pattern shop to make the tooling that the foundry uses to build the sand molds, or you could have the sand 3D printed for a few thousand bucks. But you would also have to have a design for the aluminum to flow through the gating into the mold, through the part and into the risers, with vents in the proper areas. This is not a trivial engineering task in most cases; it took me about 10 castings to get the gating, risers and vents working properly for my cylinder heads, and I had some expert help in that area.
Then, of course, the casting has to be machined. So you would need some sort of fixture to hold the casting in place while the cylinder head side was machined flat, carb pads machined flat, bolt holes in the correct location, etc. Somebody with a Bridgeport and a lot of time can probably do this, but unless you are doing it yourself, you may have trouble finding someone willing to put the time and effort into this.
None of this is trivial, which is why you don't see a lot of folks casting complex parts. Kelly has a great setup and process for doing one-off castings, but he will tell you that most of the work is in the design; a 3D model of the part you want cast is pretty much a required starting point.