Rick57,
For all the spinning a distributor does they seem to last forever. If you pull a vacuum on the advance can with a small hose and your mouth, and it holds until you release your tongue, then the diaphragm is fine...no need to replace.
The other items you mentioned are consumables and need to be renewed. The distributor drive gear shouldn't have broken teeth but some wear would be expected. I don't know if you would want to replace it without addressing the cam.
The most important items would be the condition of the cam that actuates the points and the wear or wiggle this cam has on its support shaft. Make sure the mechanical advance mechanism is free to turn and to snap back to its rest position.
Take a look at the insulated stud that passes through the housing and make sure it is in good shape and isn't grounded or touching the case.
These things are pretty bullet proof and last for years. Unless yours has suffered some abnormal trauma it is probably fine.
They make high frequency coil testers but you might have to go to a museum to find one. The best way to test the coil strength is on your neighbors yapping little Schnauzer...if he gets up after being zapped, your coil is weak.
Stuart
