You can see the colours and that form of base in Archimede Seguso's pieces. I am NOT suggesting that this is a Seguso piece, but that his work was widely copied. Here are a couple of pieces I have. The first piece I think is Murano and the second I'm pretty sure is Chribska (the label is a good clue). The colours in the photos aren't quite right, but you get the idea. The bases are quite different. The reason is that the Murano piece was blown in an optic mould but I don't think such moulds were used much in Czechoslovakia.
Hope this helps.
David