Cant help with the bolts.
I think we got that same make your own O ring kit at work and it seems to work really well. if it doesnt Im sure we can get you that O ring here stateside and swim it over.
Careful with the coolant pipe that runs accross the back of the motor its not available and I havent see any one make anykind of replacement. maybe cleaned the outside up and paint it.
Clean clean clean what you can and try and paint what you can even in the cold and all.