NMEA standard baud rate is 4800, AIS is 38,400. Not possible to combine them without a MUX. Some AIS receivers will allow you to change the baud rate down to 4800 but that often causes the NMEA data stream to become congested due to the slower speed if there are a lot of AIS targets. Another issue is AIS sentences begin with !AIVxx while the NMEA sentences out of the Raymarine autopilot begin with $IIxxx. Not sure if the autopilot will even accept the AIS data due to the beginning exclamation point. I had a Noland MUX that would error when it saw the !AIVxx sentence even at 4800 baud. FYI, GPS sentences begin with $GPxxx.