Buying windows from Marks Plastics is gonna run you about a 1000.00 bucks for your Islander. I have a great plastics guy here and am going to have him cut new windows for me out of some 1/4 plexiglass. he reccomended that I use Plexi instead of Lexan as it will not scratch as bad. If I remember right you just bought this boat correct? Does it have the vinyl headliner around the windows? If it does while the windows are out look at the plywood behind the headliner and make sure it isnt dry rotted. In my bahama 30 I have taken out the entire headliner and going to put up some teak plywoodalong the main cabin where the windows are and an easily removable headliner to be able to access deck hardware. If you want any pictures of what stuff in your bahama looks like while it is taken apart let me know.