In another thread I talked about what I ended up doing with this scored cylinder and piston. I will summarize it in this thread as well:
I sanded both the cylinder and piston with 400 grit wet and dry sand paper and 2-stroke oil. I did this very thinly, just smoothing out the
raised peaks only. I did this in a cross-hatch pattern.
I also applied muriatic (hydrochloric) acid to the cylinder with the idea of removing the aluminium transfer but in my opinion it was not necessary in this case- just the sanding was enough. I also replaced the piston rings.
I did a lot of research online about doing this (sanding + acid) to scored pistons and cylinders and it's very common practice. A lot of people end up salvaging cylinders/pistons this way. If the scoring is not too deep then it's most likely going to work as long as you don't sand off too much surface.
I reassembled the engine and also replaced the clutch (which was seized) and the machine now works very well. It starts right away and doesn't have idling problems
