The easiest way to do this would be to 3D scan the piece you want to replicate. I'm sure someone on this forum has a desktop 3D scanner that you could send the part to so they can scan it and send you an STL and possibly a STEP file of it.

Otherwise you would need to use some of the more advanced CAD tools out there such as CATIA Generative Shape Design...etc. I'm sure Fusion 360 has tools like this, I just haven't figured them out yet, but now I'm curious.

If neither of those options are feasible, you could draw up/print a rough shape of the nose and then start grinding it into shape from there. Obviously not how we like to do things, but when CAD tool licenses cost thousands and thousands of dollars it may be worth considering.