Any House of Cheviot hose in size XL will most likely fit you. If you have wide calves (say wider than 16") you may want to look at the Skye or Harris lines as these are made for large calves. But if it is just foot size and length you are worried about, any style in XL should work.

Their XL fits shoe size 13-14.5 (UK) which would equate to a US 14-15.5. The approximate height of the hose would be 18" to 20" (depending on just where you fold down the cuff).

You can buy House of Cheviot hose through the Scottish Tartans Museum gift shop.