Toby,
Here in Montana a cow/small bull bison runs about $800-$1200 and a mature bull about $2,000+, depending where you get it from. It costs almost as much to have the bison processed as it does for the animal, $700-$1,400. If you have the hide processed it runs from $600-$900, depending on the size of the animal. Head mounts will vary with the size, pose, and taxidermist, average is $650 and up. I have had friends travel from California for the sole purpose of getting their bison meat. I split one with my hunting partner each year (the wife and I can only eat half of one in a year.) and we alternate who kills it every year. Last year I used a 58# Osage selfbow, hex pine shaft, and 190 grain Grizzly broadhead. Placement of the shot is a lot more important then an extremely heavy bow weight.