Yes - Herrod's do an exhaust for AU's, and they also do tailor made to your vehicle. Send them an email for prices, etc.
Can't help with sounds though.
Following from
www.herrodmotorsport.com :
6 CYLINDER
SEDAN AND UTE.
We make systems to fit EA falcon to AUIII all are 2.5 inch mandrel bent, all sedan and Ute systems direct bolt in and come with all hardware and gaskets including tail pipe tip. All parts are Taylor made to suit the vehicle and can be fitted with minimal fuss. All systems are flanged witch makes fitment very easy. Our dyno testing has shown up to 8-10 kW at rear wheels.
Should you have any further questions please email Herrod Motorsport.
herrod@ozramp.com.au