It all depends on how worn it is. If it's just starting to play up, the noise is only there from cold. It should make a diesel like noise, (for those technically minded; it sounds like all the tappets went to kingdom come).
If the noise persist more than 10 seconds, and you want to make sure it's the variator, rev the engine slowly. The noise will then disappear just above 1800-2000 rpms.
if it's really shot, the noise will be there all the time, and performance will be slightly degraded.
There's no harm done, running the car with a shot variator. If the timing belt is up for a replacement in a year, I'd wait an have the whole thing carried out at the same time. If your doing the belts, taking out the camshaft and replacing the variator is only a 30 minutes jobbie.
As for the prices; I think the Dealer (stealer) is a bit on the expensive side. The specialist have got it just about right, assuming he's changing the belts and pulleys as well.
I have said it before, you might want to check out these two webpages, as they're European, and this forum is American oriented. As much as we love the yanks
they have no clue about the newest range of Alfa's as Fiat pulled out of North America in the early 90's. Check out ;
Alfa 147 page and
Alfaowner.com
Cheers
-- Hoygaard