I think the Ruger American is the best of the American bolt-actions that can be purchased for less than $400, but if you are considering rebarreling, I wouldn't bother for anything less than a "standard" U.S. made bolt action rifle.
Ruger M77 or Hawkeye
Remington 700
Winchester Model 70, etc.
If you absolutely love your American, then go for it, but I don't think it will ever be worth what you would have invested in it.