Another alternative is a Shub retractable shower screen.
SHUB - RVs/Boats - Newline International
Not a door, but will work in an RV. One MH manf. was considering going this route. Shouldn't be a problem finding something that will work. I'm not a huge fan of the glass doors, but have had several. The retractable screens kind of offer the best of both worlds. Kind of like a door, but retracts completely out of the way unlike the door, and it's not a curtain.