30ft Cavalier re-engined with a 18hp Witchard Diesel. I have a reciept for $7k from 2002 which is before I owned the boat. I believe it used to be a BUKH as I can see sections missing on the bearers where the big flywheel sat.
Engine hasnt missed a beat.
The owner Johhn is also v helpful. An Ozzie owned and run buisness.
www.wm-diesel.com/
Thanks Cav30
Personally I wouldn't spend a cent on the existing motor. The old saying good money after bad. Over heating suggests the possibility of a lot of issues including cracked heads etc. I just wouldn't rebuild an old raw water cooled motor that has already been rebuilt.
Spend 7k on a new Beta and fit yourself with some help. If you have the money why worry that you would be spending more on the motor than boat is worth. If this means you can rely 100% on that motor for next 20 years it's gold.