Explaining both of them together would definitely make you feel that there’s only a slight difference between these two words. They sure overlap each other very often.
However, sourcing and recruiting are completely different. Sourcing is the process of looking for candidates directly by using pre-screening tools such as applicant tracking systems (ATS).
When you hire a recruiter for candidate sourcing services in Australia, you are going to hire a person who is going to look out for candidates as per your described job brief. They would simply conduct pre screening, for instance, checking out their portfolio, resume, etc.
Then they would turn in the details to let the client make the final move of hiring. However, recruiting is known as the entire process of sourcing, screening, recruiting, and sometimes onboarding candidates for the client.