That looks good. Did you do the finger nail trick Blasterboy said. I agree with him if you run your nail up and down the walls and you dont feel any scratches you should be good.
How is the piston play in the cylinder meaning the fit? If you bought a new piston you should take it to a shop and have it sized to your piston if it needs to be.
Very true. From what I can see in the pics, you should be OK with just a new piston and rings. HOWEVER, put an old ring into the cylinder and measure the end gap with a feeler gauge. The gap should be within spec or a couple thousandths of an inch out. Measure it at the top, center, and bottom of piston travel in the cylinder. If the end gap is .002" out of spec or greater, you will have to get the cylinder bored out to the next oversize. If your jug is stock as of now, going .020" over should do it.
Just know that if the ring end gap is OK, and you opt to just install a new piston and rings, I strongly recommend that you have the cylinder honed. Honing breaks up the dull, 'glazed' finish you see now. The process also roughs up the cylinder wall just enough to help the new rings seat. If you don't hone the cylinder, the engine will still run, but you will have more blow-by and get less life out of the 'fresh' top end you just did.
That's my experience, anyways. I have been made to 'overhaul' a couple Kohler engines at work by a boss who doesn't believe in honing cylinders. I later found out that one is still running, but it smokes when started b/c the oil rings never did seat properly. The other twin runs OK, but it doesn't have the power it once did when new. Again, all because it was put to work without honing the cylinders to allow the rings to seat.