Why black anyway? Only relatively recent LB's (of the last couple of centuries, lawn archery and sporting bows would have black buffalo horn tips).
The traditional bow would have used cow horn which can be variegated, half and half, streaked or plain, brown cream, grey, white, transparent, most anything except plain black.
Nothing wrong with using deer horn if that's what you have, the bow after all is osage not yew, so why worry about faking the appearance of black buffalo nocks?
Bit stiff in the lower limb, better at full draw than at brace?
Rod.
