Replacement for Hitachi LR135-31 alternator?
 

Go to www.balmar.net. Their smallest alternator, the 80 amp model is what
you want. Any more amps will be too much for your small engine. But that is
more amps than a 220 amp battery bank should accept. So either dial down the
amperage with their MaxCharge regulator or add another battery. I would
strongly suggest the later.

David