There's timing marks on the block and on the flywheel. You set the timing with the shims to put the marks where the factory specifies. If you change pumps you should use all the old shims and then check your timing. Your new pump may need to add or remove a shim but will probably be in time.
I don't know how to check cam. I would very closely inspect the lobes while turning motor and also look for any obvious hanging up or more pressure required to turn it. I am surprised the cam is not obviously marred. It might be just throw a new pump in there and see how it goes.
If the cam seems okay and you get a new pump definitely change the oil and do whatever you can to make sure any metal debris gets cleaned out. Fill it with diesel and slosh it around then drain it or something before you refill it and new filter.
Keep us posted.
I don't know how to check cam. I would very closely inspect the lobes while turning motor and also look for any obvious hanging up or more pressure required to turn it. I am surprised the cam is not obviously marred. It might be just throw a new pump in there and see how it goes.
If the cam seems okay and you get a new pump definitely change the oil and do whatever you can to make sure any metal debris gets cleaned out. Fill it with diesel and slosh it around then drain it or something before you refill it and new filter.
Keep us posted.