I can't say with certainty if this is a nuisance caller; I have in contact with persons from people all around Australia.
However, the (08) extension suggests that the caller is in Western Australia - and I've not spoken to anyone in Western Australia in my lifetime!
If it's who I think it is, it's a foreign telemarketing company routing their service through Perth. I have been contacted from (08) 9468 4229. They are possibly routing through Victoria also, from (03) 9020-0325.
If you get calls from any of these numbers with a 'British-sounding' telemarketer offering insurance of some kind - they're linked. Further, all of the 'victims' either seem to be, or have been OPTUS customers.