Give things a good scrubdown with solvent and a stiff-bristle brush, and hone the cylinders just a little with a button hone. Wash them out with hot, soapy water and rinse well, then reassemble it. I don't even think I'd replace the rings- - - - -they look brand new. If you want to be absolutely sure, do a re-ring job, but don't worry about rod bearings.
Jerry