Ramman,
As you noted, the owner's manual says not to use ATF-4 transmission fluid in the power steering. If you go to any auto parts store and check the shelf with the power steering fluids, you will easily find several brands which claim to meet or exceed Chrysler's (and other manufacturer's) OEM specifications. You'll also have a choice between regular, synthetic, or a blend of the two.
Best regards,
John L.