Thank you for all your responses and sorry for my late response.
I am at the work at the moment and will post the dimensions this evening.
I think the width is approx. 25 cm.
The seller I bought the piece from was trustful to me.
So I don't have doubts.
The crack is from one to the other side of the foot.
It looks like the foot was dismantled and repaired.
I have contacted Bukowskis. Ms. Seeman believes that it would reach a price of approx. 4-5000SEK.
It is a great bowl and I think I will not sell it. The damage is invisible if the bowl is standing.
Possibly I will start to collect scandinavian glass, too.