Any bowl needs to set flat to the floor without rocking. Shim as needed, though we tend to shim the back and try to pin the front of the bowl to the...
You would be looking at the Vespin II if you wanted to go with the 14" Unift adapter.
Same tank, but a different bowl that allows moving it back 2"....
If the plumber needs to meet the local codes, he is not going to give you a choice if you want the pan, expansion tank, and any other things needed. ...