Rebuilding one of these engines is expensive. Yes there are sleeves available, but these are dry sleeves that are used at the machine shop. They are not replaceable in frame like those in a Cummins or other wet sleeve engine. The sleeves are available so that you can repair a cylinder that may have been ruined by some sort of rod breaking mishap.
Your best bet is to bore to the next oversize, and use NEW pistons and rings. The crankshaft is hardened like most all diesels and unless there has been a run with no oil incident in the engines life, you will most likely not have to do anything to the crankshaft.
With the shortblock properly bored and put back together, the success of your rebuild is all in the head. Replace the valveguides no matter what. If the cam and followers look good, you will probably be okay leaving them. It is easy to replace the camshaft at any time anyway.
Best of luck, and keep us posted on success,
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