inserts.... like the flounder pounder stuff....
 

so i removed a small insert box, port side next to the seat. it looks like a cell phone insert. let me back up here. i removed the box to access inside the gunwale to bolt the antenna mount. the cut out is rectangular, 9 3/4"X4 1/2". it's cracked here and there so i'd like to replace it with something. i have no clue what. worst case, i'll re-use it.
flounder pounder didn't have anything and i couldn't really find anything on ebay.

Charlie, go to Flounder Pounder Marine and type in fire extinguisher insert.
Is that what ur looking for?

phat, it's almost what i'm looking for. if you cut it in half and it's the size of a drinking glass.... that's what i'm looking for.
if i have to, i'll cut it out and mount a fire extinguisher as there's currently no mount for one.

Maybe make something out of starboard?