Nancy Fratti handles an assortment of worm wheels as well as worm
gears.  Check with her to get what you need.

The new gear may not run smoothly until it is worn in.  Make sure that
the worm wheel is well polished to a mirror finish where the worm wheel
runs, and this will greatly aid in the smooth starting and running
of the mechanism.

I quite often put a generous helping of Brasso in the mating area
of the gears and, with the governor assembly in my hand (not on the
machine), I run the first wheel with my fingers or on a smooth soft
surface, to speed the wearing-in And mating of the two components.

Make sure to completely remove any residue before final assembly.
Good luck.

Dan Wilson