Using circles for sketches on different planes, create Catia "Multi section solid".
Fillet the end.
Mirror the solid.
Done!
In a lot of other software, it's called a "Loft" or in some, it's an extrusion through multiple sections. Catia terminology doesn't really translate to... well, pretty much ANYTHING else, in my experience, even other Dassault software... if I knew CATIA better than I do now, I'd probably cuss it less, but as it is, I cuss it very much.
Anyways, OP, whether you want to add a 'draft angle' to your extrusion or draw the half-section and revolve it - likely depends on the dimensions you have to work with. Do you need to make it taper at a certain angle? If so, draft angle on an extrusion will be easiest. Do you need to hit a certain diameter at the end, with a certain starting diameter? Then it'd be equally easy to draw a section and revolve it, OR create a circle at each point in space and extrude/loft the circles together as a solid. This gets into the whole "Modeling your part with 'design intent' " which is another chapter... but I digress.
I have not touched Mastercam since... ~2003/2004, so I can't really help you on specific "how" but the terms (extrude, loft, sweep, draft angle) should get you where you need to be in the HELP file, assuming you installed it, and assuming their Help File is worth a shit. It should at least get you to find the button and play with the options/settings. The part looks pretty basic, so it should be straight forward once you find the right buttons to click.
Add a radius/fillet to the edges as needed after the overall body is modeled.