Win M70's are my favorite action to build off of. Great factory triggers and simple, simple actions with less working parts in the whole thing than a savage bolt. I also like the 3 position safety and bolt release on them. You should be able to find an action in the $300-$400 range.
You will need a magnum action if that is your intended purpose.
My 6mm-06 built on a classic push feed.
.223AI on a M70 push feed