In general, we do not recommend cleaning oxygen sensors and then reinstalling them.  The extremely high heat of the exhaust system tends to weaken and in some cases all but disintegrate the sensor’s threads.  It’s not especially uncommon to be lucky enough to get an O2 sensor out in one piece only to have it fail upon reinstallation.  (This is why there aren’t “oxygen sensor cleaner” dips or aerosols on the market.)  In short, we understand that they’re not cheap, but we still in good conscience have to recommend purchasing new sensors.