[Zeke]

Certainly I was thinking of a single unit that had all the features of the above and the lower railing at an elevation that was helpful to aid in stepping in an out of the tub as well as providing 'garg bar' support. I like your sketch or a variation of it.

Anyway, you're close enough at this point that you don't need me. If you have any doubts about a final design and dimensions, use some electrical thin wall EMT to mock up what you want. The railing fabricator can use your pattern to bend the final product. I did this making a roll bar for my 914 race car. 1/2 inch bends easily with a bender or over any sturdy round object.