It does sound like a Model 38 carbine. The 1941-XIX is the date it was made for the Italian armed forces by Beretta, located in Gardone, Italy. (Beretta is very much still in business and the U.S. armed forces now use a Beretta pistol as the standard sidearm.) The 1941 is obvious; the Roman number 19 was part of Mussolini's effort to "restore" the glory of the Roman Empire. One of his ideas was a new dating system beginning with 1922, the year of his March on Rome. So 1941-19 is 1922.
I am not sure what you mean by a UN number. The letter prefix would be part of the serial number, not a reference to the United Nations.
Value of those guns runs around $150 or so. The cartridge is relatively low powered, but is adequate for medium game, like white tail deer. They require what is called an "en bloc" clip, not a stripper clip. The clip holds six rounds and is loaded into the magazine. Clips can be had from
www.gunpartscorp.com* or at gun shows. Ammunition is (or was) available, but expensive.
*Their catalog calls it a stripper clip, but that is an error.
Jim