Due to milky oil in the counter balance chamber dis-assembled motor, the counter balance is completely rusted seals/bearings ruined. Looks like all the seals and bearings on the pull starter side need replacement. The clutch side of the crankshaft looks good no apparent residue in the main crankshaft compartment. Can I leave the main bearing and seal on the clutch side intact w/o replacement?

Does the Main bearing require any special lubrication?

Suggestions on good place to obtain the replacement parts?