O-Ring for access plate

[JohnB]

All,
I need to find another o-ring for the rectangular splash well access plate
on a 88 23' Sceptre. Any ideas or suggestions?
I am down to about 5 little things
to fix on the 23, but it is an fantastic deep water boat.
Don't mean to brag, but I was out of Sebastian Inlet
last Fri, and the only other boat out there that followed
me in was a very big Contender. We came in thru 4-5
foot seas at 21 mph, and actually was pretty comfortable
and dry.
Thanks in advance.