That Franken saw is a mis-mash of 026 parts, some that don't function together.
You need to sort out weather you want a compensating or non-compensating carb, then get the proper cover/filter/tank vent that work together.
The cylinder and cover match up for a cyl with decomp. Some monkey scratched up the piston with a sharp object as seen by the ex port picture, the vertical marks are something the saw ingested, came loose, or from debris left inside when the saw was worked on. You can look for casting marks on the base of the cylinder to see if it is OEM, there also should be an A or B stamped on top of cylinder denoting size.
I can't see an adj screw for the oiler from your picture. As mentioned you can pull the clutch cover/ drum and see if the oil pump has a drive wire to the drum.
The original starting problem, could just be that the choke was not functioning due to the cobbled up air filter, as it started with (cringe) ether.