I'm paying 125 USD per cubic metre for RoRo. Los Angeles to East Coast Australia. You can do the math for your truck. Go through a shipping agent rather than directly with the shipping line. 20ft containers are an option but the loading and unloading fees added onto the cost almost equal RoRo.
Make sure you shop around a bit, because the prices can vary considerably. I paid 53 Euros/m3 last year for my mog via RoRo from Europe to the east coast of Canada. I know, the distance may not be the same, but it'll give you an idea.
Here is a link to several companies that go between Hawaii and the States:
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