Custom exhaust is probably going to be your best bet then chief.

Pick a good shop, take them samples of the sound you want and get them to make one. If they're any good they'll happily tweak it if it's too loud or not loud enough.

I totally adore my F355 exhaust, so much so i'm gonna move it over to the Mk2 project, will be bit of a mare plumbing wise but worth it.