You have to have a "good reason" to legaly EDC a fixed blade in England.
Reasons include, work, religon, part of a national costume.
The only knife you can Legaly EDC in the UK without a reason is a folding knife ( penknife) with a 3" sharpened edge length blade, or less, that doesn't lock.
Think swiss army type slipjointed knife. There are lots of UK legal knives to choose from now that fold without a lock.
Sorry didn't want to turn this into a lecture, you probably know this already, I just thought i'd let you know before spending £$£$ on a knife you may not want to have conviscated and be charged for. Dont get me wrong, I regulary EDC a large locking folder, but I have a reason to use it when I have it. When I dont, I have knives that are legal.
What do you plan to do with it? Would it be a heavy user or something to carry and use on an occasional basis.
I've always liked this for a small fixed blade, prehaps just a bit to short for you though.
http://www.noze-nuz.com/benchmade/bm210ggt.php
With $400 you can get a lot of good fixed blades, or one "pimped out" knife. Good news is though there are hundreds to choose from.