It always helps if you tell us the year etc.
If you have a 98 SVT, the cable end is available by itself. It is a dealer item. You cannot buy it at a parts store. Depending on the catalog (there are several catalogs available for Ford dealers -- Ford outsources this, they don't print their own) you may be told that the part is not available by itself and you will need to buy the entire cable set).
I would recommend that you call Bill (I can't remember his last name at the moment), the parts manager at Team Ford in Las Vegas. He knows the correct part number and can ship it for less than your local Ford dealer will want to sell it for.
Depending on how it failed, there may be an easy fix. If the rubber bushing wore out, you can take the bushing from the new part and install it in the old cable end. It takes some strong finger and thumb pressure but it is doable. This saves you the hassle of removing the old end and adjusting the linkage. Removing the old end can be difficult if over time the portion of the cable end that stays with the cable (the black part) warps and will not release easily. If that has happened, you will need to cut off the old (white part) end and trim or grind the black part to allow the new white part to slide over it.
If the white part has broken, you have no choice but to replace it.
If you have a 99 or 00, this is not likely to have happened as the entire cable set was redesigned. The cables are not as stout, but the cable ends were a better design. The cable ends are not interchangeable between 98 and 99/00.
As a temporary fix, you can secure the cable end with a nylon cable tie. When mine broke, I drove it for a couple of weeks or so until I had the replacements cable end.
Others have had success with finding some other bushing (I couldn't) to use, some with a thin washer and a "C" clip of the correct size to hold it together.
If you do a search, you may find where some of this has been posted before.
Good luck and tell us how it works out.