Two-speed Falcon automatics show up on e-bay fairly regularly.

I just did a quick glance at e-bay and saw a Ford-O-Matic transmission for a 260 V-8 listed. See: https://www.ebay.com/itm/FORD-1963-F...wAAOSw9-Va0PmH

The 260 transmissions had a different torque converter than what came for the six cylinder transmissions, but everything else is probably the same.