According to the chart you found you are correct. In the US it would be a D or E size hook. I looked at the picture and the pattern and the size of the hook while though small is correct. The shells formed are small and not large. You could go up a hook size if you want the shells to be bigger. Otherwise hook with US , D or E, which is 3.25 mm or 3.5 mm.
>> I does look since it is an old pattern that back then the women didn't have the sizes in hook selection that we have now and while we would use a larger hook than they did then they made do with what they had.