First off, where does the oil seem to be leaking from? If it's near the front of the motor it may be the timing cover, which I believe is fairly common. If your willing to live with it it's not a major issue
in my opinion.

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00' C230K
88' 190E 2.3
79' 280CE (Sold)
84' 300SD
73' 450SE
93' 300E
68' VW Bug (what the hell was I thinking!)
99' HD FLSTF