Hi, interesting, but have never seen one like that.
The one ahremck refers to on 20thcenturyglass site is number 1479 which has often been attributed to Aimo Okkolin, I suppose, simply because its shape resembles the one of a known Okkolin design called Stromboli. I do not know if there is any official proof of it being more than just one of the large number of export vases from Riihimäen Lasi having been sold as unattributed.
I personally would not bet for the resemblance between that known Riihimäen export design and the one of this thread. Looking closer at the lower part the shape is different, the possible satin part which is unknown to RL designs and not the least, the huge size!