I hadn't seen this colourway before, and only found two others when searching, so I thought I would add it to the board as one to look out for. These vases were designed in 1936 - amazing really, when you look at most other glass being produced at that time - so the 70th anniversary coincided with the 125 years of Iittala in 2006. 6.25" tall and a hefty 1612g.
The website below states that these were made to "...commemorate the 70th anniversary of Alvar Aalto’s historical design. The outside of this remarkable vase is a white (opal) glass and inside is cased with an [sic] forest green....".
https://www.finnstyle.com/white-green-vase.htmlNB: The piece is also clear cased on the outside.
I have no idea what they say about it on the website below, but if you scroll down you can see it in 5 colour variations - green, blue, orange, navy (or maybe black), and one that looks like mustard. Hopefully it doesn't say you can buy them from China!
http://blog.lumiukko.jp/news/新作情報/28317Its really hard to see, but there is a small acid mark of the logo and Iittala on the base, as well as the label on the front.
Whilst researching this, I came across a couple of copies of the Iittala 125 years book for £200+ and £300+, which had me eyeing up my copy......until I found them on Amazon for £40+!