Hi Mike
From
www.rc-champ.co.jp the site is in japanese but they respond in English to emails. It cost :
Upgrade kit 5880 YEN
Spare boom 630YEN
Spare belt 980YEN
Hatori 540 pipe 4875YEN
Hatori header 2400YEN
Postage, tax and paypal fee = 4331YEN
It arrived in 3 days but I had to pay UK VAT and duty totalling £30GBP as it was sent using speedpost, will know to use air freight next time!
Cheers
Ian