Maybe a 142E is rare and valued in the US, but old Volvos in New Zealand aren't really saught after

Well, the US is not really seething with crowds anxious to buy old Volvos either. ;-) That's reflected in their price, which tends to be way below that of lesser quality but far more charismatic heaps. The 140 series is a case in point: their numbers are much reduced because people believed Volvo when they said "Drive them like you hate them," and promptly did so and then send them to the crusher. Even so, the 140s are the least sought after of all the old Volvos around here. "The forgotten Volvo" we call them. The 142E, however, is a little tiger of a different stripe, and not all people who like old Volvos are aware of that. It had the high compression B20E engine and it succumbed to emission regulations after only one year of production. That's what make them so rare and appreciated among the conoscenti. I may be wrong, but I doubt that many made it to the NZ scene, and yours may be the only one there. You probably already know all this, but this is just in case you didn't. Far be it from me to presume to tell you what you should do, and the car may,indeed, be too far gone to be worth saving. Shipping to the US wouldn't be worth the cost. A clean GT might be a different story. Now, if you are going to part it out, and if the 142E badges on the fenders are in good shape, i.e., have their little legs firmly attached, I may be interested in buying them from you.
Bob S.