Is the seal leaking? I had problems way back. The collar adjusted to the carbon sleeve where water enters for cooling. If the water pressure from the engine is high it will cause the seal to pulse when the engine is running. Just put a valve to throttle the flow and pressure. Had everything replaced when the boat was brand new. It leaked and this is what we found was the solution. This boat has diesel engines.
The stainless steel collar can be adjusted for compression to the carbol cooling block.
My dripples packing is the orginal on port engine and I had to adjust it three times. From your pictures I doubt you needed to nerw seals.