I'm not sure if they're made in Spain along with the barrels, or produced at the A/H plant in the NAA production facility. Quality wise, I'd guess that they're spanish made, but I don't know for sure. I have 2 Mountain Rifles and 2 spare locks for them. They seem to be of good quality, but not up to the standard of what the NAA factory is capable of.
Sorry I couldn't be more help. I'd like to know for sure also.