Looks like the keel has the "catalina smile" (crack between forward part of keel and stub) which is not uncommon, but will need to be repaired. Maybe some other rust and weeping elsewhere on the keel, but hard to tell from the photos. Keelbolts look good (common for them to show more corrosion). Also the rudder shows rust and weeping at the top where the post connects--may have had a saturated rudder?--at the least that would have to be filled.
Thought the rig looked nice, from what I could see, mast in nice condition. Maybe even had the stainless spreader bracket upgrade? But check the chainplates, especially on the other side of the bulkhead (not pictured). The bulkheads appeared to have water damage where the chainplates bolt on, so I'd poke around that wood really good. Not uncommon for that bulkhead and/or chainplate to corrode and need replacement, due to worn out sealant on deck.
I know it can seem like a lot to have this boat surveyed by a pro, but if you're seriously considering her after looking into everything, it's worth the peace of mind.