The routing looks OK. The rules do allow for taking surface sections, although you have to include the mileage between them in your totals.
Re: fares: I've just paid ~$5,900 CAD booked through SQ for a Business Class fare. The price seems to fluctuate with the value of the dollar, but I'm not sure what the base currency is (US$?). Last year it cost around $6400. Don't know the Economy fare.
Somewhere recently someone posted the fare rules published by NZ, but I don't recall where the thread is.
Any TA can do this for you, or you can book through an airline.
FYI: The more recent rules don't count the US and Canada as one country for departure/return. It doesn't affect yoor trip, but now you can't leave from SFO and return to YVR.