They are definetly sleeved. You can buy the entire rebuild kit from perkins
but you will have to contact them first and see if they can provide a "build list number" if you don't have it in your documentation
. They will probably be able to do that from your serial
number. The serial
number is just a block number, the build list number provides all the details, turbo or not, three rings or five rings etc.
These engines were built in so many configurations the "build list number" is a must. if you are really lucky you'll have a 5 ring version good for about 20,000hrs. before rebuild if properly maintained.