Don't take this the wrong way but if your rifle budget is only $400 then you don't need to be shooting a 30-378 Wby magnum. You are going to spend that of 5 boxes of factory ammo.

To answer your first question the vanguards / Howas are excelent rifles. You would be hard pressed to find a better rifle for the price tag.

And to answer second your question.... there isn't a $400 rifle chambered in a 30-378. New you are looking at at least $1500 on up.