At 13.5" I have a narrow calf for my height and foot size (5'9", 9 1/2 M sometimes a 10M) and struggle to find boots that don't look ridiculous.  I knew these ran large so I ordered the 9M in dark brown and they are gorgeous.  Quality is amazing (expect the bit of usual Frye heel slip) and best of all, the calf fits!  I tried them on with socks, but I also have room for skinnies/leggings.  They are a casual fit so are not snug through the ankle, but they fit like this style of boot should.  If my 12" Frye harness boots (I needed an 8.5M in those) are any indication, these will last forever and just get more comfortable with wear.  Even though the investment is a bit daunting, they are so worth it.