73-76 Slant Six K-member

I'm looking to update my '67 Dart 270 to disc brakes, and I want to do it responsibly. The idler arm currently on the car can't handle (safely) the upgrade.

I'm wanting to buy a K-member from a '73-'76 A-body with a slant-6 engine. I don't want the engine, just the K-member. (If it happened to have disc brakes, I'd be willing to buy the spindles and other assorted brake parts, too!)
I have the K frame