Cost for replacing fuel pump?

I have just a fuel pump replaced for my 2003 Ford Focus at Javis which is a big Ford dealer in South Australia. They wanted to change me AUD1150. I refused to pay the price and found bought the part by myself but they still changed me 4 hours labor which is AUD396 ( after discount). Does it need to take four hours to change a fuel pump? For my previous experiences, Javis normally quote the price for the parts much expensive.

Labor is charge by man hours which is the standard rate

Replacement of the fuel pump requires that the fuel tank be removed to gain access to the pump 4 hours labor sounds about right. Hopefully the new pump you purchased will not have any problems. If you buy the part from the mechanic who does the installation, and the part is defective, the part and labor are both under warranty. Seeing as they installed a part supplied by you, if there's a problem with the part, you will have to pay the labor again

I'm in America. So I'm not sure. Over here it costed me $900.

Sounds like they had to remove the gas tank to put the fuel pump in it. That can take a good 3 to 4 hours.
Check to find out if your car had an inspection port to get to the fuel pump. If it has one they should only have charged up to 3 hours labor.
Here in the USA youtube has automotive informational videos. Do a search there for your vehicle if you have access to youtube.

The amount of time a customer is charged isn't necessarily the time it actually takes to do a particular job on a particular vehicle. This is an average time to complete a job and is determined by industry standard labor guide and states the time allowed for a competent technician to complete the job properly. Dealerships most generally charge significantly more than independent shops do, for both labor and parts.