Fix it! Unless you can find a shaft cheap. They can be repaired by changing the u-joints where bad. Take the wheel off and rock it back and forth while listening for your clicking. U-Joints can be changed by using two sockets, one to drive out, the larger to receive.
I had a clicking on my right rear that was driving me crazy! It was suggested (on this forum) that it might be a loose brake pad. I pulled mine, shimmed them closely and applied some of the silicone stop squeal. No more clicking!
BTW, it doesn't take much "slop" in the pads to make a click.
I'd think it would be worth trying before you start swapping halfshafts.
you shouldnt have cv's on a 240.. only the 83 2+2's and turbo zx's got cv joints. so if you do have them someone swapped them in and you can get cv's rebuilt with a lifetime warranty for about 40 bucks per.. if you have the ujointed halfshafts you can change them yourself.. not easily but it can be done.. it just takes alot of banging..mine clicked after doing a few donuts and a new ujoint fixed it.