200k on a civic engine is not big deal if it has been taken care of (and sometimes even if it hasn't been taken care of). First thing is to do is get that slave cylinder bolt fixed. Next would be a compression check and/or a leak test to find out how your internal engine is doing. Once you've done those then depending on the results, you go on.

As for the rust, it depends on where you live. I'm in Arizona so rust can be slowed here and the car can live a long time, however if you are in a snowy area or close to the ocean that may be a different case.