What do you mean by high end, and do you want a flexible or stiff knife? The model by SamuraiStewart looks very nice.
Do you want custom or factory made?
There are a number of factory made boning knives by companies like Bark River (Kalahari Sportsman in S35V), Falkniven (VG10), and Warther (S35V). I use a Warther fillet knife in the kitchen almost daily.
In addition, Japanese knife makers offer boning knives, and some models are similar to the conventional American style boning knife. I am thinking of Tojiro (VG10) Gokujo, and other companies make a hankotsu. I can't recommend Shun, but I do like Tojiro (and their models are inexpensive).