I cannot remember a Maxum rebuild recently, so this should make for a good thread. There has been Internet hearsay about Maxum boats not having any wood in them, but I am not sure what year range that started.
If you can post some pictures, that would be good to let us see what you are seeing and to offer advice.
Like the others have said, it would be best to get the old floor up and see what the underneath looks like. Boat usually rot from the keel upwards, it is rare to see that just the floor needs replacement.
No need to place material orders yet, as that will be based on what you find when you have the floor opened up, etc.
When the time comes, you can get some stuff right here on iBoats, but for more extensive material US composites is a favorite. I also have used fiberglasssite.com