This was tricky and after going around every plumbing and hardware store in chch, i went to a boating shop and they had exactly what i was after.
This is a water tight bung that can be undone by hand.
I plan on rounding down the edges so it is not so intrusive and save my feet from being chopped up on it if im unintentionally hanging ten.
I installed the plug by screwing in place and sealing it with resin all over. If you have built your board using the hollow web method be careful were you drill your hole, as it can damage the supporting struts on the inside.
