http://www.rockislandauction.com/viewitem/aid/67/lid/1635

Just as production of the .32ACP Type Hamada pistols was reaching full scale, Bunji Hamada was asked to redesign his pistol to use the standard 8mm Nambu cartridge. This he did, and after several changes required by the Army (which appear to have had more to do with giving the Army some claim to the design rather than for any practical reasons) it was adopted in 1943.

Production of the .32ACP pistols continued uninterrupted, while a defunct textile factory in Notobe was renovated to become the production plant for the new Type 2 Hamadas in 8mm. Machinery was provided by the Torimatsu factory, and the guns were to be sent to Torimatsu in the white for final finishing operations.

While several thousand were made according to surviving records, the only ones still known in existence today have serial numbers between 2 and 50 and are still in the white. This suggests that aside from a small initial (sample?) batch, all the Type 2 Hamadas were destroyed or lost - possibly by aerial bombing or during transit on the ocean.