I was considering this Varta 2.4 volt, 200mAh:
http://www.dhgate.com/product/...75543507.html#s3-3-1|1972515394
(Watch me catch the devil for the link format.)
Curious that you should mention the NW2, Bob D. I'm converting a SW1500 (which I asume is virtually the same) from 5-volt to 3-volt, and find it quite cramped. It used a 1.75"/45mm speaker, with a very flat magnet (speaker depth is under 10mm)hanging in the compartment between the trucks, and with a 3-volt board, there is no real space for even a AAA.
Anyone know what the mfd rating is on a BCR?