So... How do you get the .22 liners? I see what you mean. Looks like a project like that is best for someone that really wants to do it, and has the tooling and expertise to get it done. Having the barrel correct externally is also a plus for most. For me I would rather it shoot as well as possible.
If a man could become known for making such a conversion by making enough of them, they could become collectable in their own right like the Neiders. Keep on making them and mark them as your creation. All you need is a reputation for quality, and time. Someday people will be collecting your rifles as unique and valuable pieces.
Now I want a lathe. lol I want to do it too.