Calling all MAC exhaust gurus !!!

I've got a MAC 4 into 2 exhaust up on ebay right now and I want to make sure I'm not going to screw somebody over. It's NIB NOS, says kz650/kz750 on the side in Jiffy marker, part number 9020309.

I'm hoping someone can steer me to an online resource where I can confirm what models this thing fits, before I actually sell it to someone that can't use it.

Although the little lady has voiced a strong desire to have it on her ride...