71 k20 differentials?

[gun_hunted]

Hey all, my 71 has a dana 44 up front with a gm 10 bolt in rear. I was told by the guy i bought it from that it has 4.11 gears in it. Im looking to change them out to 3.73's but im not sure if i can find that gear size for the rear. My other thought would be to find a set of newer axles from a wrecked 4x4 and swap em out. Any ideas or opinions on what would be a better move??? I also wouldnt mind getting a rear exle w/disc rakes either