I have a 2000 civic lx it has the drum brakes with metal tubes. I was curious if there is a replacement for the tube for a actually brake line. One of the tubes is rusted and squirts fluid. I saw there's the main line replacement ...I was just curious about the tube.

 

Yes. Plenty of options for aftermarket stainless braided lines which are cheap. Just google it.

Or you could do something like this:

https://www.ebay.com/itm/284256055833

 

I did everything that came up was not to the drum itself

 

Looks like the only solution is to upgrade to disk brakes. Didn't want to leave the thread with out my solution

 

You could buy some straight brake line then bend and flare it yourself. It looks like a pretty aggressive bend, so you're going to be lucky if you can do it without kinking the line. After you spend the money buying the right tools, you're probably even (or over) what it would cost to find an old mechanic to do it for you.
Only other option I can think of would be swapping to disc brakes as you stated.