If it's cracked on the end, as shown in the above picture, just weld it. It's not heavy structural on the end. It probably cracked as a result of rust pressing the joint apart. A guy could make the weld repair right on the truck w/o having to remove it: ....1/2 hour to grind the rust off, weld, and hook back up ...with even a little time to spare to put the tools away. Zero $$ parts cost. Done.
If the crack is in the center or corner, then it'll take a gentler touch: I'd remove, Vee, weld and quench. When I was a kid I custom bent a few custom front anti-sway bars to fit 60's cars I had. You know how those cars would tilt to a 30* angle going around corners?? I used 1 1/8" torsion bar from those old FWD Toronado's, which there were quite a few in yards back then. At the time nobody (I was aware of) was making HD anti-sway's for 'classic cars'. They worked great and I never had one bend out of kilter no matter how many times I put the cars into the ditch.
Back then ......once I finished making a thicker front anti-sway, I would take the old stock 60's front sway bar (usually 5/8") and re-fit it to the rear suspension. My cars cornered darn flat back then, when everyone else's was wollowing around corners! LOL.
In your case, if the crack was anywhere other than the very end, I'd Vee the crack, apply heat to heat up a broader weld area, make the weld, apply more heat to heat the broader area, then gently let it gradually cool down a little. Then quench the area in oil. That's how I would go about fixing a cracked Ram anti-sway. Even if you didn't pre-heat ..just welded it cold, it would probably hold up just fine. If it doesn't hold then time to buy a replacement. But my money is it would hold just fine. That's one approach to take anyway..
