The button's could be reversed if one desired. Here is how they are normally ordered:
Left handed seems to be the most popular but I have had a few orders for right handed sticks.
I talked to UberArcade a while back on the topic of making left hand joysticks and he said he always did the primary button on the inside, secondary to the outside of the stick, but I guess there's pros and cons to either arrangement.
I'd like to add your joysticks look wicked sweet. Also PM sent for Donkey Kong!