I bought an entire suspension kit from Performance Suspension Components in AZ. It came with Hellwig bars. I have already installed the rear and currently have the front suspension torn out.

One note on installing a rear bar when there previously was not one installed. There were 2 options on how to mount the innner mounts to the frame rails. If your car was origianlly equipped, there are tapped holes with tapping plates to bolt to the bottom of the rail. If those holes are not tapped, you use a sandwich bracket on the sides of the frame. Mine were not tapped so I bought nuts with an integrated flange, drilled out the holes and welded the nuts in place. Its a much cleaner look than the sandwich bracket.

I think Ricks First Gen carries the Hellwig bars.