To quote someone else:
"Jukar was a company in Spain that was one of the first muzzleloading gun makers exporting them to the US after WW2. Jukars were imported and sold by Dixie Gun Works, Navy Arms, and CVA among others. The Spanish MZL firms Mendi and Jukar merged in 1980 and was then called Dikar, who I believe is now owned by Bergara.
Usually their arms would bear proof marks from the firm Eibar, which I believe was the official proof house for Spain, who has been making arms for 500 years. Apprentices from the gunsmithing trades at Eibar have gone on to have successful careers at prestigious firearm houses like the famous Holland & Holland in the UK."