Paul, I made a few phone calls and both the 3203 and 5203 would have to be ordered. Not a big deal, but I decided since I already had a 6203 in my supply I may as well use that and just plan to change it every 500 miles, or approx every 2 years. The 3203 and 5203 are $50-60ea while the 6203 is $8. I figure I would be pulling the cover off every few years regardless so may as well just keep replacing my 6203. I may search around to see if there is a 6203 with a nylon cage so at least if the cage fails there is not metal being ground up in the gears. Those must be some tough gears because after eating a few cages there is no damage.
