I admit I was basing my shipping comment mainly on how I've found USA-based companies tend to behave when shipping overseas to me Rosco.
I'd expect a bill of
at least $US200 for a USA company to ship a radiator to me.
And by the word "shipping" I include the associated cost of "protective packaging".
If a radiator could be shipped reliably from Australia to the States for just $90 then that would make it worth considering. But I would be surprised. (I would have expected more than $A90 just to get it reliably to New Zealand.)
In comparison with a radiator, an injection pump is compact and damage-resistant.
But then again .... I'm always being surprised by shipping costs

Some eBay sellers in far off lands amaze me how cheaply they can ship. However I do think cheap options for bulky easily-damaged items like radiators must be very limited when you get down to actually doing it.
And if a company is asked to choose a cheap untracked shipping method, they obviously won't take any responsibility for non-delivery or damaged-delivery.