Garry, you want top notch work??
You want a custom knife???
I will echo that you can get a very nice knife made on BB, or you Could try Allan Blade, Gene Ingram, Stewart Marsh, Paul Baker, Bearclaw, Bison Bushcraft and the list goes on and on and on.
The best Custom Knife that you can get in my opinion is................
One you make yourself and yes I am totally serious.
1).If you go to a maker he will make you what he can supply, not neccesarily what you want.
2),When you make a knife yourself the handle is made for YOU and not anyone else, it is also made in the materials that you decide to make it from.
3).If you cannot make the blade that is no worry, there are literally hundreds of different blades out there that you can use, Lauri, Fallkniven, Puronvarsi, Helle, Frosts, Pedersen (Trond) and Brusletto to name a few.
4).Cost, you may have £150 to spend on a nice new knife, but for that cost you could make something awesome and that is totally unique (there are no identical copies of it and never will be).
5).The sheath can be any design you want in any materials you want.
6).In making it you have just added another string to your bow.
You would be amazed at what Neil1 can put together for £300 in the way of kit.