Is the diameter of your bowl 28 cm? If so, it's pictured on p. 292 of Designlasin, which has most, if not all, of Wirkkala's designs for Venini. There's a bowl and a big vase. There's no name given for the design. The description (it's in Finnish) says something about different production periods affecting the value, which would be consistent with your label and signature.
Asking Venini is the best idea. Nice piece, btw.