Well, depends what you call Spanish, I suppose. There are a number of early Portuguese (and English) guns on the Santissimo sacramento, wrecked off Brazil in the 1660s; the cannons are now scattered round a variety of instititutions in Rio. They are published by Joe Guilmartin and can be found on the internet.
I think there is an English gun cast by the Mayo brothers inthe 1550s in Massachusetts. Queen Maryt of England was the wife of Philip of Spain, so could count as "Spanish".
But there was a facetted gun found in the Gulf of Mexico, dated 155? which was being touted round in the 1970s; it was certainly published in the IJNA, not sure where else.
Oh, and my wife says, to let you know, she featured two of your items in her last Basilicoe Mercury; she hopes you don't mind.
Bob Smith