Are you asking about Cobras or 427 Cobras? "Early Cobras..." implies one thing and curved shift lever implies something else.
Cobras, leaf spring chassis cars CSX2001-CSX2589, used gear shift lever and knob assemblies that were short and straight.
427 Cobras, coil spring chassis, CSX3002-CSX3360 used curved lever assemblies turned around forward.
1963 design versus 1964 design lever assemblies: lever assemblies are not the same and the easy to spot difference is the shape of the finger grips for the reverse lock-out mechanism. The 1963 design grips are thin curved (and easy to break off) while the 1964 design grips are straight with angled tips in a much heavier cross section.
1963 design versus 1964 design knob assemblies: 1963 has a one piece black knob used with a thin hex chrome plated hex jam nut while 1964 has a two piece knob, an upper portion in black and a hemispherical chrome plated lower section.
427 Cobra shifters were very different, long, bent, and angled. Here is one in a CSX3101-CSX3200 car.
The Shelby American purchase order list is not being helpful because the part number listed is for a sub-assembly containing a lever assembly, rubber boot, and knob assembly as a purchased unit. The order list does not breakdown what pieces went into the purchased pre-assembled group.