Honda CR250M 1975 to 77 cylinder & head, 70.25mm current bore size, no rust inside clean and probably usual at that piston size.
Comes with a new Wiseco piston & rings set ( 70.50mm )
Can send pictures to your email address if PM is sent to me.
Cylinder and head will be bead blasted prior to shipping.
asking $275 which about the price of a new piston kit plus postage to new owners address.