even though the 60-63 had 1 more year of production over the 64-66 the latter seems to be more popular... maybe there were higher production #"s on the 456's...?
regardless there seems to be much more available for the 456's than the 60-63's..
all you can do for the door is buy a door skin , and a lower door patch panel, or find a good dent/rust free
-good luck
- 60 - 63 door-htf.