Try Maplins-or Electrex ( http://www.electrexworld.co.uk/ )<br /><br />A plain 2-lead rectifier will be cheap and should have a heatsink on it from them so may last longer. You might find you can use one with a built-in regulator as well which would be a pretty good safeguard for your battery, though I'm not sure if the voltage output is high enough for this to work. Check physical dimensions too or it might not fit...
