Hi
My 26 "CLEO" has an Yanmar gm 7.5 hp which was fitted new in 1982 , the engine still runs beautifully and starts almost first time every time except for a few times when she has been left for a few more weeks than normal.
I often think that with its age she will need to be re-engined at some point in the not too distant future.
the yanmar gm10 is a great engine however it is a single cylinder and the beta and "Elsa's" Lombardini are twins so much quieter and modern
i have looked at several at the boat show and there are a few good deals to be had!!
Have a look at the Beta and Nanni, they can supply adjustable mounts to fit mose replacements and are basically the same engine. i have been quoted boatshow prices for basic engine of approx £2400.but nothing i writing !!!!
good luck
i would be interested to see what you go with
Peter Lowry
CLE0 ss26