Seeing niscourt's post, perhaps this is a better source.
Mercedes W123 mudflaps set of four used | eBay

The bodies of the 123 and 115 are similar enough that perhaps they would work.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).