What types of starters are there for Chrysler 318 engine?

There are two types of starters. The 2875927 starter is for a rear mounted starter on a CCW engine.    The direction of the
engine is from the back looking at the flywheel (LH)

The 2875928 starter is for a rear mounted starter on a CW engine.   The direction of the
engine is from the back looking at the flywheel (RH)

 Most marine Chryslers have a rear mounted starter, meaning that the nose of the starter,
faces the bow and the starter is behind the flywheel

Most non-Chrysler marine gas engines have a standard mount starter that the starter nose is towards
the stern with the starter being under the block and in front of the flywheel.

Both of these starters are available.   They are remanufactured ones from Alco (who may
very well have made them for Chrysler back in the day)