You can buy 14 pitch gears online, but surprisingly made-to-order gears seem to be cheaper somehow. About 8 years ago we went down this road with a friend, and got his gears reasonably. I'm sure there are more options now.
on the parting I didn't see what your spindle speed was, forgive me if I skipped over it somehow. one half of the equation is making everything more rigid. the other half is reduce pressure by lowering RPM and using the sharpest possible cutter.
One trick that made parting FAR easier was to move the blade slightly below the centre line. On my 12" lathe for 1" cutoffs, was .002 - .003 below centre.