I've got a Oz phone that's locked (it's a prepay).

I've tried dialing Telstra's unlock service but it doesn't seem to be reachable outside the Telstra network.

And the prepaid has run out of credit.

Assuming Telstra doesn't answer my email to them (likely given my experience of their customer service) any suggestions for an unlocking service in NZ? Most of the ones I Google look international and a bit suspect.