The TOTO Drake works at 10-7/8"
The round bowl would be 26.5" from wall to end of bowl on an 11" rough.
Their taller bowl, C744EL is elongated at 28"
That fits with either the ST743S or ST743E tank.
There are also a few tall, round bowls, but I'm not sure what the back clearance is.
When you are sitting down, the knees are in the same position regardless of whether it's round or elongated.