94 Cougar 4.6 Please Help!! Starting/running issue

My 94 cougar with 4.6L has an issue. The mechanic looking at it said the "air plenum" is busted up and ford/mercury doesnt make the part anymore. Not really sure what the part name is, but he said its a plastic tube with 6 or more inlets for vacuum hoses. Basically he said the tube is where all the vacuum lines plug in. He can get the car to start and run by plugging off the vacuum lines but it wont idle. What is this part called and does anyone know if it can be purchased new or remanufactured?

About 7 years ago the car ran fine, then on the coldest day of the year it stalled. When it is cranked over it backfires. We tested the computer for codes and had none. Installed a new fuel pump and filter and checked the electronic coil packs as well. This is my moms car and she just parked it. Now she wants to get it running.

Any help would be greatly appreciated, I hate to junk a perfectly good car with less than 100K miles because of this one piece.

Look at the part you need and make a trip to the scrap yard and buy a used one.
You can also call ford parts and check if it can be ordered.