I have an old bike where the rear wheel was so far out it hit the frame (chain stay) on one side. A couple of days ago, with my trusty Park "0" wrench, I was able to straighten it to an acceptable condition without even removing the tire. I am absolutely not an expert at this type of work, but I've done it before. The one I speak of is the worst I've fixed, and I honestly thought I'd need to break down the wheel and bend it back to shape before I could get it true. According to Sheldon Brown, a novice will likely do more harm than good by trying to correct with spoke tension. But I can attest that an experienced bike mechanic should be able to fix your wheel, and probably for less than replacing the rim. Again, I consider myself a novice, albeit perhaps a lucky one.
Fantastic bike, by the way. I hope your son does rock this on Campus. And I hope my kids follow suit. My toddler already has an old Hedstrom trike with double white pinstripe tires (probably early '70s, and an early '80s Ertl pedal tractor...