just get regular marine grade fir plywood
epoxy it and be done with it
if you plan to have it a long time, coat it with 3 coats of a thin enough penetrating epoxy to begin with once it is fitted. Then glass it in place.
The United States Constitution does not exist to grant you rights; those rights are inherent within you. Rather it exists to frame a limited government so that those natural rights can be exercised freely.
1984 was a warning, not a guidebook!
It's time more people spoke up with the truth. Every time we let a leftist lie go uncorrected, the commies get stronger.