This is the Japanese white label promo version of Symphony In Blue. There is also a standard issue release of this single, but with red and tan coloured record labels that are similar to the early UK releases.
The earlier Japanese singles featured some really eye-catching graphics on their releases, and it's one of the main reasons why they used to appeal to me so much. Japanese and English text always feature on the back of these picture inserts, which usually included a small photo or two.
Although Japanese singles were issued in a green Toshiba EMI company sleeve, white label promos tended to be issued with a plain white sleeve instead.
Most people refer to this sleeve as the Dolphin Sleeve, It's quite rare these days, and quite expensive now. So you can expect to pay through the nose for a decent copy of it. updated this post on June 12, 2011 with additional photos.