I would see if you could get a skid with a Gaylord on it. a Gaylord
is a tri wall fiber board container. Plastic MFG & metal parts mfg
usually have these. You could use banding material or bolts to secure to skid but don't use nails; they work loose. Sometimes
frieght companys have theses also. Also you must rember that it must be delivered to facilty that has a dock and proper handling
equipent( pallet skid etc)
Since Seattle is a major port of entry try one of the many
freight forwarders or LTL (major) located there.
Check about draining the oil & fluids too because you possibly could get stuck with a major bill for Hazardous material clean up.
Most major carriers will now put the trailer on train's now
for shipping this distance. Maybe you could try someone like yellow frieght/CF etc
Chuck