Checking before I purchase new tires

A 215/65/15 should be 26" tall. That should fit just fine with a 4.25" backspace.

I had 225/60/15's on the front of my Duster on 15x7" with 4.25" backspace and had no rubbing issues. I wouldn't have been able to go taller because the front corner of the wheel opening would have hit a taller tire, but the Dart wheel openings have more space on the front corner. It'd work on a Duster too you just might have to trim the very corner of the wheel opening a smidge.

GmachineDartGT runs 255/40/18's on his Dart, those are also a 26" tall tire. And a heck of a lot wider.