Julie Nilsen wrote:

I was hoping you would respond, Gary. It isn't
painted. It's natural wood that has been sealed
I believe. It may have to be painted though.
I'll see what the other responses are and try
To figure this out.

Sorry so long to respond. Sounds to me like you either
need to paint it all or replace at least one section.
You'll never be able to sand that out for touchup.
Good luck getting a good match to the other sections
though.

I suggest you call first a few painters and see what
they say and get (free) estimates to restore. I don't
think it possible. That stain goes deep. I wouldn't
take that job as I know it won't come out perfect.