[quote=Katabasis]
No matter what, though, I'd really like to have bolt-action rifles, even if they're relatively new and not widespread.
[/quote]

Bolt-action rifles, at least breech-loading versions, were available as early as 1840, so you should be fine. There wouldn't be clip-loaded/or magazine-fed bolt-action rifles like the Springfield or Mosin Nagant though.