Hi, I just saw a front swaybar on ebay the other day and it was made by some manufacturer in the US and damned, I can't find it, (maybe bids closed on it) but it was made special for the 63-64 full size Fords and Mercs, and the price was reasonable too. The size was one inch in dia. and kit was complete with the bushings and end links. One other recourse is to try locating an old Merc or Ford station wagon, now I'm not sure but I've heard they have the heavier sway bar.
I just replaced the old worn out bushings on my 63 Galaxie and that sure made a big difference even with the stock size bar. But I would try ebay again. I'm sure there is a demand for the heavier size. Those bars are all the same shape for the full size Mercs and Fords of that year. Also try asking the director of our Galaxie club. firstname.lastname@example.org