Dear Bilinda,
You do have a collectors item, sort of.
What you have is a Bar (Bodegas) commemorative display of a product from Casa Francisco (Now it is known as Bodegas Francisco Casas, located in Navalcarnero, Madrid) Casa Francisco and the other “Bodegas” suppliers would supply the Tapas and Bodegas with table wines to be sipped, while standing , at the many wine bars and Tapas stands that dot the cities. What you have is a commemorative display, probably to celebrate the anniversary of their new vineyards/estate that was built around 1965 – If it was the 25 year (which sounds right because the used copper (looks like gold) or it could have been to celebrate the anniversary of King Juan Carlos.
What you have is no different than a neon sign, without the neon. The proprietor would set the case up at the back of the bar, you would ask him what it was and he would tell you that it was an anniversary edition. You would then drink a toast to whatever anniversary that was celebrated. I think that it might not be for King Juan Carlos, because then it would probably have an image somewhere of the King and Queen.
The reason it is collectible, is the proprietor would usually get the display for free, so when it was done, they would throw away the bottle, and maybe keep the leather case to hold receipts or tips.
The wine, as the label says, is a fine table wine. Further, the label says that it is 1/2 gallon. Keep in mind that it is not in liters. So it is just that, Gallo! The collector part is the actual case. Chances are that there were somewhere in the neighborhood of a couple of thousand made, some were sold at the winery, the rest were probably used to promote the wine around the world, (Notice the use of 1/2 gallon and the fact that the parts of the label you can read, are in English).
The value would depend on exacting what the anniversary was that the display was made for. It was probably the 25th and was made about 1989-90. And the total that were made and distributed here in the U.S./Canada. If you have an old Spanish or even an old Italian restaurant in your neighborhood, they might be able to assist you further.
Based on what I’ve seen in the marketplace, your bottle would go at auction for $25 – $100. Since there is a renewed interest in Spanish wines. I’ve listed the website for Bodegas Francisco Casas. You might be able to send them a picture for a better explanation of how many were made (they may not even know, since the winery merged in the 60’s) or if they have any further information.
Good Luck!
James