Hydro Systems
I have exactly what you are describing -- we're installing it this week. It's made by Hydro Systems (
www.hydrosystem.com). They do a lot of whirlpool tubs, but you can order any model without this option, and also specify the integral tile flange. Ours is 60X30 (Lacey), but even more choices available in 60x32.
All these tubs are made to order, so they're not cheap and take a while to get what you want.
Good luck!