I have imported several bikes from the States. Two WD M20's 1978 CB550 with 680 miles on the clock. The cost is very reasonable
. The bike being imported must have a title and you will need a bill of sale filled in. Customs need this to calculate duty which is only 5% on bikes over 30 years old. Sea Kargo imported all mine. Average cost of £500 plus duty. Sea Kargo ship out of Kearny New Jersey. Bike needs to be delivered there. Uship are very good in my experience.