Maxum makes the Deck and Hull and assembles everything. Everything in the boat is made by a third party (With the exception of the engine and outdrive, which is made by Mercruiser. Both Maxum and Mercruiser are subsidiaries of Brunswick).
Tables and Posts: Todd Industries
Cleats and Lights: Perko
Heat/AC: Marine Air (Dometic)
Stereo & Speakers: JVC
Just about anything on the boat can be purchased from marine chandlers. What are you specifically looking for?