Without offending anybody must say, this proceeding for a simple part was unprofessional, and thus needed many posts.
Finally it looks nice.

1. Make a hand sketch with all dimensions (from who has or wants the part).

2. In (any) 3D-CAD: draw a horitontal center line, draw the upper section of the part (2 lines closed), then revolve this section 180deg around the center line,

Done (less than 15 minutes), a nice exercice for beginners.  - SERGE -

Please don't argument: Now do it!