I would encourage having it inspected by a reputable repair center to determine the extent of the smoking. Things to consider are

1) Smoking excessively
2) Above with subtle Engine Noise
3) 1 with excessive Engine noise

Items 2 and 3 may dictate a cost prohibitive situation; however, that will be a personal decision.

Item 1 would only discourage me after I had the left side valve cover removed and inspected. Once upon a time there was an occasional problem with a specific freeze plug located on the inside front of that cylinder head. Below the exhaust gear there is a 12mm bore that runs the length of the head. If this plug is missing a smoking exhaust is imminent.