Some photos to look at as asked for yesterday and two of one of the pistons that has damage that I assume is from a dropped valve at some time in its earlier life and probably is a result of the crack down the side
The shells look ok, measure the crank journals after a clean but I would think they would be ok.
That piston damage (as has been said) is a foreign body getting in and bouncing around for a while. Not a valve.
Can we see pics of other pistons and bores.
Not sure if the “1” on your piston means 1 O/S, so the bores need measuring. Unless someone knows different.
I am used to seeing the same numbers as on your shells.
But your bores may be able to be saved with just a hone.
I have had no dealings with Turners but they do seem to be the go to people.
J