The Owners Manuals for my 1985 OA comprise 2 x large ring binders embossed "Ocean Alexander" in gold. One binder holds operators' manuals for the Cummins engines and TD gearboxes (not the originals but perhaps these took the place of the original engine manuals?). The 2nd binder holds manuals for various other items of original equipment....like the Morse controls, the docking lights, etc. The one unique OA document in the manuals I have is a comprehensive electrical schematic hand drawn by the company founder himself. Since the whole vessel has been comprehensively re-wired by me and had been extensively re-wired by previous owners, this schematic is now just of historical interest.
Since your vessel is the same manufacture year, your Owners Manual may also have simply been a collation of individual equipment manuals. Do you have anything OA-specific at all?