There also are 2nd party 1400 batteries still available for the 1400, though at a high cost. Probably the best deal out there are the ones that Wegener Media sells. They go for around $45 (see URL below). While they are new old stock, if you cycle them well, they will give about 45 minutes to an hour of use. A disadvantage of these batteries is that battery reconditioning only seems to work with Apple brand Ni-Mh batteries. So all you can do with these ones is to discharge and charge to build them up.

A whole lot easier than doing battery surgery. But, the runtime is not fabulous.

http://www.wegenermedia.com/14xxbatt.htm