A single odd ball cam out of tool steel would likely be cheaper than a single custom heat treated core. Maybe a 10 count would lower the price of the heat treat core.
I agree, A roller cam core effectively starts out as a raw solid round bar anyway in most cases I believe..
And the cam core for the OP's stated reasoning, he should research further and understand some have chosen one additional firing order swap, (2/3 swap), which is the direction I am going, and doesn't coast a dollar more on the custom cam.