I think the left picture is the '65-early '67 disc/drum spindle and the right picture is the '70 drum, but it's dark and hard to tell.
Both spindles will work with the '65 disc brake brackets (assuming 4-piston KH calipers) as the 4-hole pattern is the same
The '70 spindles are the good ones to have.
Here are the two side by side ('65 left, '70 right):
And with bearings ('65 top, '70 bottom):
The '70 spindle takes differnet bearings and a differnet spindle nut as well.
The tie rod pickup point is slightly higher up on the '70 which increases the bumpsteer slightly which isn't good, but correctable.