If I were doing the work for you, I would suggest one thing. Take that rifle completely apart and send the stripped barreled action and bolt to Marlin for a heat-treatment verification. There is no sense in buying a new bridle for a horse that's coughing. The discoloration of that receiver, in the excellent pictures you've provided, is what troubles me. And, it would be nice to check the bolt for Rockwell hardness also. Pressures from rifle rounds could be step #2 in the process of ruining a softened up ( annealed ) receiver even more.
As was mentioned above, and I agree wholeheartedly, the springs are all toast, and I'm sure the scope lenses have walked off the job also.
Dennis