IMO using 6 inch duct work is too small for the efficient movement of air. Consider 10 to 12 inches. Use a 10 inch fan on this end with 10 inch smooth duct work.
If folks will not ship, try a freight forwarder. Send to Seattle or LA which ever is used for shipments to Hawaii. Yes, it does cost more overall, but at times is necessary to get around the "we will not ship" issue. Perhaps UPS to the coast and then by ship to your island. If they will ship USPS then freight forwarding is not necessary.
|