Depends on what you want done,I can hook you up with Peter Roper if you like, but he is winding down his involvement.
His understudy Michael is carrying on, however it is a bit further away than you would probably want.
Most shops are hopeless.
Ah, the old 'my V7 suspension is trying to kill me' post.

There are plenty of aftermarket rear shock options out there but if you want to see a professional then google suspension workshops in Melbourne. We have places like Promecha, suspensionsrus, and Racecentre who all specialize in that stuff. As far as specialist Guzzi folk see this facebook link for some options
https://www.facebook.com/groups/mgcov/posts/6970733512990429/. All these are used by Guzzi club people. I've had my V9 serviced, and suspension set up by Platinum Motorcycle Repairs. They did a good job but didn't seem that keen to book me in again when I called them recently. They did a dyno tune and remapped my bike, but it caused them some hassle. It might have just been my bike though.