You can get 00 durum, if reading between the lines your recommendation is actually to use durum flour not softer wheat? Indeed 00 is often sold in the UK as 'pasta flour' and is durum wheat (or at least a mix) milled to that fineness; semolina implies durum wheat but is typically coarser (even 'fine' semolina, I don't know what number grade, other than 00 we don't use it here) - maybe that's not the case in Italy and '00' is never durum but 'semolina' can be that fine?
