This is about 2 (TWO) sets of 2 new OEM uncut keys each, with regular metal head. 
Genuine Ford part made by authorized distributor in the US.

Two keys for ignition/doors and the other two for the trunk/glove box.

All four keys with the original Ford logo stamped on the front and the "Family of fine cars" slogan stamped on the back.

You will need to take these new keys with your old working keys to most hardware stores, home improvement centers or locksmith shops to get them cut to fit your vehicle.

Please, compare your actual key with the picture. Make sure your key has the same grooves and shape.

They fit:

(1971-1974) Lincoln Mark III, Mark IV, Mark V, Mark VI