Its reall easy to build a cage out of acrylic . Im also in the marine hobby and we build alot of support equipment out of acrylic sheets and tubes etc ...
www.usplastics.com for ideas on prices and such .
Tools you will need are a saw(table , circular) with a fine tooth blade , router(maybe with a table) , acrylic cutter , a work bench and a clamps . Figure out your size of the enclosure and draw up some plans . there are a couple ways of doing it . You can cut and cement all the pains or cut a large piece and heat and bent it useing a acrylic heater jig to get it perfect . Then if you have a router table you take the bent piece and cement a piece of acrylic on the back side and router off the access with the table . Then the same for the bottom . If you want to make it so you can slide a panel out of the front you nee to router out a hole and then use stripes of acrylic to make rails .
I know that was alot of head splitting crap but I hope you get something out of it . It is a liilte work but not to bad if you have all the right tools and a place to do it .
Good luck .
