According to this persons blog on Jan.09,2011.
Japanese SUN doesnt have Helron treasure box yet.
(He has main quest 30/30, and main mission 100/100.)
I hope we will have this update soon too...but 100 of main mission... =_=; really...
Like someone had said before, in Korea you can get helron jewel
by using those 6 compass. This person said he doesnt know
if Japanese SUNs gonna be the same system...but it gotta be like that right?