I decided to add a Nambu pistol to my collection in 2012 because of their popularity as a captured war souvenir and bringback of U.S. Marines during WWII. The Nambu I ended up purchasing was built in 1943 and known as the Nambu Type 14a. My Nambu has survived in almost factory mint condition complete with one of the original numbered magazines. Compared to the United States, these pistols are much less frequently found in Canada due to very few Pacific war veterans residing here after the war.
The best single resource for anything Nambu related is Teri's website Nambu World. There's nothing I can say about this pistol that hasn't already been covered on her extensively researched website.