Thanks for the feed back and comments guys.
Mike: These are Nambu "Type 14's"
Baba: Your are correct on the dates. The system used to date these is 1925 plus the first number which is year, the 2nd number is the month.
The following site has examples on just about each year of production with a lot of really informative information, it's a great site!
http://members.shaw.ca/tju/jhg.htm