The pit you can see at one o'clock of sunlit area is discernibly felt with fingernail. I also wonder if anything has found its way into the bottom end. Almost all the pits are at the bottom end of the cylinder. The mechanic said he could put it back together but wouldn't guarantee it wouldn't seize at some point.
Every little light speck in that pic is a pit. My concern is that the plating might flake, get into, and wreck, the bottom end , and therefore the saw if I keep going with that cylinder. I don't know enough about the subject, hence the post here.
Those pits have likely been there since it was new. The pits wont case the plating to flake. Not a concern at all.. But you could drop and 357 P&C on it now and have a great saw with no worries at all.
Displacement isn't everything. It's only 2cc's, the 357 spins a higher rpm which means more chain speed. The porting in the cylinder is likely more "aggressive" stock as well. The 359 was made to hit a price point, the 357xp was a high performance pro saw. Can't have the cheaper 359 outperforming the pro model can we?
359's were "detuned" from the factory if you will. No crank stuffers, the cylinder has a blockage on the lower transfers, some models had catalytic mufflers. Add in the cheaper cylinder and you have a saw that can hit a price point but still be an awesome pro built saw for guys in the know.