Sea-Dog Scupper Valve
but it would seem the question the OP is asking is HOW to remove the water from a wave that rolls him, not really water coming in the scuppers.
I know nothing of the FJ except having seen them on the water. My Capri 14.2 had positive floatation... up under the seats in particular... You COULD swamp the boat, but it would not sink... But you COULD get enough water below in the boat, that you could NOT get it out (I won't go into the long story how I know)...
Suffice to say, I had the same problem with my 14.2, and the ONLY solution I could come up with (since the drain plug was below the water line), was to haul the boat out, pull the plug, and let it all drain out. That boat had scuppers though in the cockpit, but it was POSSIBLE to flood the cubby, and therefore essentially scuttle the boat (without actually sinking). Of course you could STILL sit on the boat (sort of ON)... but sail it? NO.
Bailing? I believe it held close to 400 gallons of water when scuttled in this way... so I imagine the FJ is VERY similar. Even with a perfect 1 gallon container and strong arms... I doubt it could be done in such a way that it'd be sailable again without a stop-off ashore to drain it.
Here's what I'd be aiming to do... Assuming you aren't planning on racing it... I'd fill every square inch of the thing between the hull/liner with foam! Make it have JUST enough positive floatation to NOT be an issue... if that don't work... use the OPTI approach.... AIRBAGS!