There is a procedure you can try while the cylinders are on the tractor to evaluate how much repair might be needed.An afterthought about this repair occurs to me: If the only reason for re-sealing the cylinder is because it’s leaking from the end... then there is little reason to replace that difficult seal on the piston at all.
Just replace the O-rings on/in the piston and on the end-piece and get-on-down-the-road. Any internal leakage at that piston will likely be resolved by the o-rings alone...and any other will be insignificant and inconsequential anyway.
This, if it my attempt to add an image works: