I have a 1973.5T in Sepia Brown here in Georgia (Atlanta). I just checked my VIN No. and its not that far off from your dad's car. Mine was bought at a dealer in Birmingham, Alabama.
I usually show up at the Avenue Mall in Marietta (east of Johnson Ferry Rd off Roswell Rd) the first sunday of each month where several hundred cars show up between 8 - 11 for a get together. Normally a ton of Porsches come by, but I am the only 73.5T Sepia in the crowd. The car was restored and looks great. Stop by some time if you want to take some photos for your dad.
Regards
Bob