Sorry for this late update, but I did speak with the repair guy. He wanted a hundred bucks for the repair, and it wouldn't even be through his doing--he was going to have "his guy" repair the slug for me. Well, I only got this typewriter for ten bucks at a thrift store, so I'm not throwing down 100 for a slug repair. My friend has a torch and solders things as a natural hobby. He and I are going to wing it together, see how it turns out. It'll be fun. Thanks for everyone who offered their opinions though! It is a soldering job, as some of you suspected, but this will be interesting.

It shouldn't be to hard, considering that the slug did not even fly off, so theres still a little bonding left (I think).
Im no expert solderer, but I'm assuming you should move the slug back all the way, and put a streak of solder on the back.

Well said, treefaller! That's how I see it as well. If it's a 10 dollar investment, why not experiment and see what you can accomplish on your own?!