I have a set of Viking shocks for the rear of my 63. They have a set for early Galaxies, may not show in their current catalog. I dealt directly with one of their reps, he said they could adapt just about any length shock by changing the upper and lower mounts as required.
However, I also have the Calvert rear shocks on my 63 Dodge. That will do a 1.54 60' with nothing more than S/S leaf springs, pinion snubber and those shocks.