1) I don't know where to find one with NITRO written on it, but how often do you think people will see the words on it? I'd recommend just going with this type:
http://www.basspro.com/webapp/wcs/stores/servlet/Product_10151_-1_10001_22508_225011000_225000000_225011000_225-11-0
Still looks good, and will meet the function that it is designed to do.
2) I'm with the others on the rod tubes. I've got a very nice looking one that came out of my Triton TR-20 within the first few weeks of ownership. It looks very nice, but I got tired of trying to finesse my rods in and out of the tubes without breaking eyelets. I gave up and now use Stick Jackets - which for me, work the best of any "rod sock" type item on the market. I love these things. Everyone who fishes with me that checks them out eventually gets some themselves.
http://www.stickjacket.com/Web/Home.php
If you still want to build the rod locker thigamabob, I'd go with "Starboard" type material and some of the aforementioned golf bag tubes. I prefer flexible plastics over wood in a boat:
http://www.rivermarinesupply.com/xcart/catalog/product_11845_Taco_Starboard_Marine_Lumber.html
HOWEVER.... if you can find a piece of it big enough, a white plastic cutting board is very similar to the starboard material, and cost a heck of a lot less.
OR... you can just trade me something for the one I took out of my boat and modify it to fit yours. You just have to get past the Triton engraving on the rear part.
All the best,
Glenn