Raw water pumps, while similar, all have a few features in common; a pump body, shaft, impeller, seals and either bushings or bearings.
This particular pump uses two bearings that are pressed into the pump body then retained with a c-clip.
To remove this clip you will need a set of c-clip pliers of the type that pinch rather than open when you squeeze the handles. Sears, and other tool retailers, sell these and they are called everything from "retaining ring pliers" to "circlip pliers" to "c-clip pliers".
Removing the c-clip is as easy as it looks. Simply insert the pliers tips into the retaining ring holes, squeeze and then lift out the ring.