DON'T buy them on-line. Buy them from a tack shop so you can try them on, and if nothing really fits like a glove, the tack shop can measure you for custom boots. If you're going to buy expensive high-end boots, make sure that they'll be perfect for a LONG time, and that means trying them on. If you buy them on-line you'll be getting them, trying them on, sending them back, ad nauseum, until you find the perfect fit. Your other post sounded like you wanted high-end boots, so take the time to get a pair that you'll live in for 10 or 20 years. My Konigs are 9 years old and will live for another 10 years, easily, b/c they're quality boots that fit so well that I love putting them on every time.
Even if you don't have a good tack shop where you live, take a trip to somewhere that you can find the right boot. It'd take you forever to do that on-line. And you don't need to go to Europe for great boots.
I really love my Rectlignes. They were the Dover brand boot from years ago. I had to go semi custom as I'm 5'8 with a size 7 shoe, and apparently that's pretty weird. To go semi was only $50 more or so.
Front inside zippers, really really stiff outers.