Well,
Picked up a Magnetron this morning from the recycle yard - $5.00 - and the guy threw in the rest of the mower as well!! It was caked with dirt and oil, but cleaned up OK and I will have to wait now until the rest of the mower is re-assembled to see if it will throw some spark.
Can't recall offhand the engine type - 92806? 92608? - anyway it is a 1984 model. If anybody is looking for bits for this engine, I have them to give away. The vertical pull starter is in really good nick, and the rest of the engine is very dirty but I am sure it has bits that might be useful for somebody.
The base is still in the electrolytic bath but is starting to look great as the rust flakes off. With any luck I wil pick up a new diaphragm for the carbie tomorrow, and may have the mower running by next weekend.
I will take some more pics of what I have done, and post them.
Jeff