Pepa,
You're more than welcome. I agree with Nando that this engine should not need rebuilding anytime soon. I understand your wanting a source for parts. Even good engines will need some help from time to time. I will see what I can find and get back to you.
Is there a model # on the engine and serial # too will help.
Keep an eye on the run time for oil changes and you should be good to go for over 5,000 hours, maybe more, before an overhaul is needed. I have a cheapo hour meter on mine to watch that closely. My Kubota wants new oil (non synthetic) ever 100 hours. I'm not too sure about this engine.
Enjoy and keep us updated as to how it works for you. BTW I gave $250 for my Kubota, and I had to change heads, flywheel, fuel delivery system and a few other bits. The Kubota is also millitary surplus. So far mine is better than I could have hoped.
Take some pictures of the engine when you get a chance. I really wish I had been close enough to get one of these as they had several if I remember right.
RogerAS