Thanks for that info everyone. I was told that the OZA479-E4 is the one but the NGK listing suggests it's for a non-turbo and NGK said it isn't available in the country. ACA recommends the OX340 but Repco don't carry it any more! They have a cross reference to a Fuel Miser product which I wouldn't be to keen on.
Does anybody know where I can get hold of the ACA OX340 please?