If you're handy, a Sony SCD-1/777ES transport section (or virtually any manufacturer's transport) can be converted to run on 12V batteries. With the Sony the motor can powered by an unregulated 12V battery & the 3.3V and 5V DC regulators for the transport electronics can be powered by the same 12V battery. Better yet, the 3.3V and 5V 3-pin regulators can be replaced by discrete superregulator units and powered by the 12V battery. This results in a big improvement relative to stock.
Dave
