Hi Susie,

This is only my personal, non-expert, opinion.

I believe in supporting the Alfa brand's growth in Australia.  This includes trusting my servicing requirements to the business I purchased the car from.  This also helps avoid potential arguments over warranty claims.
At the same time, affordability and value for money are always very important.

If you really want a 2nd source option, I can highly recommend Maranello Motors - Pur Sang in Brunswick.  They have always provided me with exemplary service, advice and value for money.  You could also check out the 'Sponsors' link from the home page, for other options, including Alfa dealers.
Alternatively, buy a few litres of Selenia Star ($19.50/litre on eBay from Mille Miglia Motors) and throw them in the boot next time you take it back to the dealer for a service.

I would be keen to hear the opinions of other, more qualified members, as I may be talking absolute bollocks.

Cheers,

Marco.

Good point Gary. 

Stick with the dealer as $300 is not a lot to pay for peace of mind and motoring pleasure.  As for the oil, it's good  -  you can probably buy it cheaper or something similar at the local auto supermarket, ... but leave your car in the care of the experts.  You are better off in the long run as they are trained in the servicing of your car.

My car is 20 years old (my economic choice) but if I regularly paid $300 for a service, I would jump for joy. Due to cars age bits need replacing and repairing.  That can be expensive. 

Even with my older car, I would not take it to anyone except an alfa mechanic professional.  A brief encounter with RACV once really caused an issue as so many people in the trade do not understand the nature of a European car.

Cheers