Need a Replacement, My 7"x 7" Post is Deteriorating

It appears you are not near the coast but....around here or in many areas where houses are built on pilings you could pick up a piece of 8x8 piling that was cut off as scrap for free. It would be ideal as it is super treated for ground contact and last a long time. I see them laying in trash piles on the beach all the time. Anyone build houses on pilings in your area, maybe because of a flood zone? Just a thought.