If I'm not mistaken, you can make Cougar exhaust pieces fit with a bit of work.....Don't quote me though, I'm not 100% positive. I know, that didn't really help, but it's all I've got...
The Cougar setup will be too short for your Sport. You can grab the resonator & muffler from him & have them welded in place of those on your system if you like his sound better.
Personally I wouldn't bother if they were stock. If he's got performance muffler/resonator combo, go for it.