The value is whatever someone is willing to pay. Many pistols were converted for use by the German military during WWII. The "full size" 1922 version was intended for military use. The caliber is known as the .32 ACP in the US.
In very good condition, it is probably worth $200-$500.
In life, strive to take the high road....It offers a better field of fire.
"Robo is right" Fuzzball