The bison looks a tricky subject.
there are templates in the book "carving animal canes & walking sticks with power" there is a template of the bison and grizzly bear in there along with other animals.
Also there is some useful info on carving fur and hair plus carving eyes.I dont think the drawings are that good but it does give a front view and side view.
Subject matter like this would sit better on a shank mounted with a 45 degree angle ,which allows the head to project forward and always looks better.
You could always down load the pic to something like word it will allow you to adjust the size to what you want which will give you a template, but doubt if you would get good side and front views.
Also you could use water buffalo pen blanks for the horns cut a slice of it boil it up and bend it to the shape you want, its pretty easy to manipulate. you also may be able to get rams horm its very easy to bend and cut
the book by the way is a Schiffer book for carvers by frank russel lots of hint and tips in therefor rotary carving .i got my copy from amazon
Its very american in the approach to carvingand theres 15 project in it and i am ashamed to say never tackled any of them He uses pentacryl for carving green wood soaks them for 24 hours. to stabalise the blankof a horse.
he explains how he prepares carving blocks which could be done with a jig saw.