Personally I would want the insides painted shiny if I went to the trouble and expense of replacing the strips with stainless and the wood floor with nice wood.
Sometimes you have to tap the available resources. Are there any boat shops on the island that paint? If you did all the sanding and prep you might find someone to shoot the pieces fairly reasonable.
Another thing you might look into is an automotive paint store that will custom mix paint and put it in spray cans. It would take some careful spraying and color sanding and buffing but it could be done.
I've used International Harvester spray paint to paint parts of farm tractors I have had to repair when I worked on a dairy farm and it works pretty well.
That might be an option for the inside of the bed.
http://partstore.caseih.com/us/ms-50...-p1769242.html The red I used held up to farm workers with a pressure washer so it's pretty good paint.