My Drift boat doesn't have a Fish box either. I have a big Rubbermaid tub with a top and keep my life jackets in there till I get a fish(sometimes I don't catch em') Then I put the Life jackets under the bow and stick the fish in the Fish Box. I seen you can get some sleek under the bed boxes for under $20.00. I seen some other models that look pretty nice and will fit under the seat for $13.00 easlily. They come with lids too. I have been looking at Walmart and Lowes and home depot. I forget which one at this time, But they all carry Rubbermaid Products Or was it Sterilite. They'll all have something that should work.
Let's see, Keeping the fish cold. I also carry a Little ice chest about an 8 qt'er. I keep my cold beverages in there and Sandshrimp so they stay fresh in there. I fill that up with ice from home and If I'm lucky enough to catch one I dump the ice in there, Voila, Cold catch, At least till I get Home.
Bleeding the fish, If I'm close to home I wait till I get there or if I'm away I'll do it someplace that looks safe and out of the way. I have used burlap bags but they seem to stink after a while. I wash out my box after each catch with Dawn liquid dishwashing soap and have a fresh lemony smell for the next time I go out there.
Smily