Suggestions on mounting raw water pump

[Capt Chuck]

Seen PVC board mentioned a couple of times lately. What is it and where do you get it? Also is it like starboard?

NO, Not like Starboard.

Rigid Polyvinyl Chloride (PVC) board

It has excellent corrosion and weather resistance. As well as a high strength-to-weight ratio and is good electrical and thermal insulator as it is fire retardant and self-extinguishing. It has many usages. PVC foam board has many of the same characteristics of wood that it easily sawed, bonded, nailed, painted,caulk sealed, joint and hot moulding. I glue mine with the same PVC pipe cement. Can't do this with starboard.
Some Sign shops carry it.