Coach manufacturers under one million dollars?

In the price range you are seeking there are four manufacturers that I would consider. They are American, Entegra, Newmar, and Tiffin. I put them in alphabetical order because which one is "best" is a matter of personal preference. Newmar will give you the option to customize more than the others but at a price. Each of the four has their own advantages and disadvantages.

As others have said, you also have the option of redoing your existing coach. Nice to have these choices.