Hello!
It seems odd that a component such as this would be discontinued and unavailable through the Ford dealer parts distribution system when the vehicle is only 8 years old, but I guess it can happen.
If it is unavailable new, you can always order a used one. If you check your lockl yellow pages under "salvage yards" or "automobile parts- used" you can find listings of nearby used auto parts dealers/ junkyards in your town that you can drive to to pick up this type of part. Alternatively, there are many internet based salvage yard operations that will ship you this type of part in the mail. To locate the exact part you are looking for, you will need to contact some of them directly, as there are often slight differences between model years, etc... so they often have some questions that must be answered by you to make sure they are sending you the exact part you need.
Here are a few of the larger internet based used parts suppliers:
https://www.woodfins.com/start.asp
http://usedautoparts.everdrive.com/?gclid=CO-d2Y27gpECFQspFQodwjRCFg
http://www.car-part.com/
http://www.partshotlines.com/
I am sure that at least one of these suppliers will be able to ship you the part you are looking for. Typically, the upper intake manifold is called the "plenum", and if you can find a number cast into the old one it is sometimes helpful to the parts supplier when checking to see if they have one available.
Service Manager
25+ years experience as a professional technician ; ASE L1 master Technician