Carey,
Trickel used to make some lead wheels, but they were not very good for running the train. I have found that the gears on these small engines are the same as the gears for the MEW spoked electrical wheels, with those wheels being only slightly larger in diameter. Therefore, I have been re-wheeling the entire engine with the spoked wheels. I believe that I have had to slightly trim the fiber piece that surrounds the brushes for clearance of the larger diameter wheels.
Here is a photo of a similar motor that I re-wheeled with the spoked MEW wheels
Carey, a note on your engine... It is missing the black side-frame piece shown on the engine above. See photo below
NWL