I have an Alpha 3000 and it has been great to me, but it does not tack automatically. I have found 2 old phone #''s that you could call. Alpha Systems,Inc. Reno, Nv (800) 257-4225 or I bought mine in Seattle at "Emerald City Marine) (206) 547-8171.
I removed a 1985 model Alpha 3000 autopilot when I purchased my boat because the main control unit was badly corroded. I still have the mechanical drive unit which worked fine when it was removed. Let me know if you have any interest in acquiring it as a back up unit.