I believe that the Douglas barrels do not have "made in USA" stamped on them.
But rather the Spanish made barrels would have Spanish proof marks on them as required by Spanish law.
USA made barrels are not required to be proofed.
This sales ad for an old CVA Mountain Rifle states: "There are no Spanish proof marks on it so it was made in the U.S.A."
And their photos basically only show a serial number, CVA company identification, and its caliber stamped on the barrel.
https://www.riverjunction.com/z-Sold...el_p_3989.html