If I read your question correctly, You want to put the SC block in 200 and take the 200 engine componets (sleeve. piston etc) and put it in the SC block. I have never tried that but I do know that when ordering overhaul kits for the various 123 engines the correct block number does make a difference.
The current 200 engine block is damaged beyound repair...in my oponion.
I would put the 230 engine in the 200.