thanks to everyone for their help. I've had a quick look through pressglass-korrespondenz but can't immediately see anything similar (though my German is not so good, meaning I can't navigate through the site so well!) I think I may e-mail Siegmar directly, he has helped me identify a few items in the past...
In the meantime I will try to get some better pictures and continue researching - i'll post any further information on the vase as and when I find it.
Sorry to disappoint you, Pamela but the vase isn't for sale as yet. In fact, I bought the vase both because I loved the design and was very intrigued by it as I had no idea of maker. I am often fascinated by designs I don't recognise as, for me, one of the most rewarding aspects of collecting is researching a piece and learning more about it. For these reasons, the vase is currently proudly displayed with my favourite pieces. If this changes and i do decide to sell, you'll be the first to know.