My Old Evinrude 9.9 Had an Alternator!
When I bought my '89 Hunter 23.5 (a great boat!), I purposely exchanged the Tohatsu outboard for a long-shaft Evenrude 9.9 with electric start and an alternator so it would charge my combo deep cycle/starting battery while running. I had it for 4 years and powered my lights, auto-pilot, radios, etc. Do your due diligence with the outboard dealer or write/contact the motor manufacturer.