Seems i've been searching for the much sought after 6900MNM in the wrong place. At last count there were 45 sellers (of the 6900MNM) on Rakuten.co.jp - all but one SOLD OUT (there is just one seller on Global Rakuten of this watch). These sellers included some that sell on Global Rakuten. I take it from this, that these sellers DO NOT WANT overseas customers when they use the domestic Rakuten.co.jp site.
You learn something everyday. Nothing new I suppose from the experienced Rakuten buyers here.