Replacing the barrel should be way down the list. This rifle has a bedding problem. Take the advice given concerning the action screws as step one. Step two will be glass (epoxy) bedding. If that doesn't work, sell it.
If the above doesn't do it, I would run some tubs Final Finish bullets through it. If that didn't make it shoot then I would consider selling but this rifle WILL shoot once you determine what is ailing it. Sometimes they just take a bit of fiddling.
