shipwreck part

Hello I have this door/hatch made into coffee table. This was my dad's that he got in Florida. The info he got was it originally came from a shipwreck of Spanish galleon. I haven't been able to verify. Any help would be appreciated. I love it and would like to give the correct info when people...

This piece was found today in an area of a reef flat where parts of a shipwreck were reportedly found in 1884. There is a metal pin & a rounded recess close to the pin. Whilst we find it impossible to tell what it could be, we're hoping someone has seen similar pieces & could possibly shine some...