There is a plan B and also a plan C Steve,
Why not get a replacement tip. get the holes brazed (with the safe stuff) and then re-drill to whatever you want? IMHO, the native Giotto tip is one of the best I have ever used.
LaSpaziale spec a 4 hole male tip (on the vivaldi, I think??). Braze 2 holes on this to make a fantastic tip....