This is what the Blue Book of Gun Values has to say:
MODEL 1922 or 10/22FN - 7.65mm (.32 ACP) or .380 ACP cal., modified Model 1910 with 4 1/2 in. barrel, longer grip frame and mag., made for commercial sale as well as military and police contracts. Several hundred thousand made by Nazis during the occupation of Leige, Belgium 1940-44. Mfg. between 1922-83.
100% 98% 95% 90% 80% 70% 60%
$275 $250 $200 $175 $150 $125 $110
Add 150% if .380 ACP Waffenamt proofed.
Add 15% for A prefix serial number/
Add $100 minimum for special contract markings.
The model 10/22 and M1922 are the same pistol. The Model 1910 was modified by FN technicians for sale to Serbian armed forces in 1923. Also sold to France, Holland, Germany, Greece, Turkey, and other countries.