My Murray lawn tractor is a 14Hsp B/S, 42" deck, model # 287707, Type: 0225-01, Code :9310274A. I understand that some of these came with cast iron cylinder sleeves. I want to change mine out to get better performance from my mower.

Hi,
It can be rebored, but it is not like an ag tractor where you can drop in new cylinders. The block is cast to and around the current cylinder.
Peace,
Clarke