oh shit

Hey guys my 690 died on me after 35000km

my bike ran low on oil once due to worn exhaust valve stem seals that wasnt picked up in a service (stopped riding as soon as the warning light came on) but when she died she had done another 3000km and was full of oil seems a piece of the piston broke off and went through the valves. Anyone seen a failure like this before? The bike is busy being re built have you guys got any advice on what I can replace while its open to ensure she keeps going for as many miles as possible

Cheers

George