Don't buy anything. Your school has copies of all of these books in text - if you're that gunho - read it in the library. Your school very possibly has electronic access for all of them that you could download and read on a screen/phone/whatever at your convenience (and in some of the electronic copies the imagery are "full" quality so you can zoom in on the little 2x2 image that is useless in the textbook and actually see the anatomy you need to see. Read a few of these books for free and potentially buy the one that makes sense that you would want to read again. I could not stand McGlamry's a few years ago - much preferred reading Mann. I've since come around to appreciating it, but if I had bought it in the past it would have been a doorstop. Also, I've read Christman's original book cover to cover and I'm not convinced that book is a must have.
I seem to recall a classmate of mine told their family they needed money to buy McGlamry's and then used the money to buy a cat. Probably got more joy out of that arrangement.