You could rebarrel a Rem 788 in .30-30 - but collectors would skin you alive for doing it. You could rebarrel a Savage 340 easily and with no collectability qualms, but 340s are a bit clunky and require a side-mount scope. I like my 340 in .30-30 and have an aperture sight on it, but I don't hunt with it; it's strictly a cast bullet range plinker.
I can't think of another bolt action that could be modified, unless somebody could rework a rifle in .303 Brit. or a Krag. Bolt actions and rimmed rounds are just a difficult proposition, mainly due to feeding issues. Rims are much more compatible with single shots and levers.
