Exhaust Pipes

My son's 2001 V6 'Stang has a flowmaster cat back dual exhaust system. Recently, one of his tailpipes rotted through and he is having a bitch of a time finding replacements witrh 3 inch tips. He's tried the local auto parts stores, even contacted flowmaster, who said they just don't sell the pipes.

Any ideas to point him in the right direction?