What seems to be the problem? Is it the barrel shelf that has been filed too much? What calibers are the ones that don't fit? The shelf on the barrel can be welded up and re fit. It is time consuming though, and you need to know how to Tig weld, or know someone who does.
If you are throwing in the towel on these barrels, let me know, I think I can find a home for them.
Nick