Complex sentence: The Olympus OM-4, an improved version of the OM-2, was manufactured from 1983 to 1987 introduced at US $685 list price for the body alone.
Split into simpler sentences: The Olympus OM-4, an improved version of the OM-2, was manufactured from 1983 to 1987. It was introduced at a US $685 list price for the body alone.