IS SOMETHING WRONG WITH 340 LIFTER BORES

As said, run a lite hone down the lifter bores. Then scrub some fine Scotchbrite through them in a circular motion to get any rust out of any pitting in the bores. I only mention this as you don't want rust particles floating up out of any rust pits in the lifter bores and scoring the lifters later.

Then measure the bore diameter carefully and accurately. You don't need lifter bores that are .003-.004" worn or more that will leak out a lot of the pressure from oil galleries due to a loose lifter-to bore clearance, and lower the oil pressure through the rest of the engine.

From the grey coloration of the crud on the cam, and the light rust all over, it looks as if there has been water in the oil in this engine. If the reason is unknown, it may be a good idea to have the block pressure tested before going too far.