You are in the ball park, but it could go up to 4 grand once done. You (we) are asking for a custom intake that is not in stock. Clearly the price would fall if you are going to mass produce it with jigs.
I think the reality is, that if Don goes ahead with the higher head design due to the pre-work that has been done, I feel Don should entertain intakes from custom manufactures so he has options for his head buyers. It would also validate the project and give options to his customers along with some assurance that there will be a complete packaged options at the end of the rainbow.
From a manufacturing and business standpoint, I would go with a single plane intake with a removable top section so you can swap out from single to dual quad low rise configurations. That would make a lot of sense.
__________________
|