http://www.sdeibar.es/index.html

I found this website. They seem to be a Sporting Goods distributor. I found soccer stuff, but I also found a couple of links to Firearms like Norica and Tekniker. So I don' t think they are a manufacturer, but a distributor only. And, unless you read spanish (which I don' t) you' re not going to get alot of info on it. Maybe one of the other members here that can read spanish will help you out by checking out this site.

If they are that eager to pay you some good money for it, I' d definately hang on to it until you find out more about it. It may be worth alot more than they are offering.