Assuming that a custom cast of your own animal is used, and from the 3 people I referenced, a ray of this size would be $350 (avg) at normal pricing for a 2 sided mount which would include a base.
This will definately be a 2 sided mount, we just havn't discussed the layout specifically yet.
Of the people that quoted me these prices, only one of them I really felt confident in...especially when it comes to the eyes.... I know of no other creature that has such a unique iris structure in the eye.
I'll post up a link to some of his work soon.
Mike