The 2004 model year transmissions were known to have problems. The factory transmission fluid had a friction compound missing in the fluid. That led to transmission failures around 80KM.
The other issue was that the solenoid pack started acting up at 240-250 KM.
On top of this (if the transmission has never been serviced) the fluid (if not low) has probably broken down enough to cause internal wear on most of the components in the transmission.
The fluid and filter should be changed every 120,000 KM at the most.
You might get lucky if you can find a reputable transmission shop in your area... and just a fluid and filter change is done.
Beyond that... this could get expensive if a rebuild is needed... or another option is to have a shop locate a used transmission from a salvage yard, and hope it works.
Some Ford dealers also can locate a factory rebuilt Motorcraft transmission, but they cost about $3000, and that doesn't include labor.