The Paris one was built out of concrete in 1991.
Officially the 20K ride only had 12 subs, but an ex CM recollects there were 14 built for some reason. 12 was the maximum that could be run, but the ride would eventually cascade with a dozen on the ride path. He recollects 12 would be on the ride path and spur, a 13th kept in dry dock and the 14th was used for spares.
It was documented two subs were sent to Castaway Key back in the day, and third was cut in half originally for D-MGM. Add the complete prop one seen backstage at Epcot and that would indeed be 14, if the 10 pictured at the landfill were indeed all buried. Which is something we may never know.