Is this tuning machine off center? (Side load issue)

There might be a little bit of an angle but it could also be an optical illusion from the camera position. I don't think it's anything that will cause problems.

 

Pleanty of basses have less than optimal streight line from the tuner to the nut. If it sounds good and doesn't habe tuning issues you are good to go.

 

Here are photos of my American Deluxe P, and J.
These are spectacular instruments, and have not given me any trouble at all.
I think it's normal for there to be a slight angle from the nut to the tuner post. (Or, they all photograph this way).

 

It might become straighter once the E string is tightened more, or settled in. It does look like it's not quite tight to the tuning post. That slight angle I wouldn't worry about one bit. Really there are a lot of basses that some angle there, and some even have a ridiculous angle. Even though it drives my OCD nuts, I'll play it. But if it was my build they would all be straight.

 

Of all the things I might worry about relative to an instrument, that would be close to dead last.

 

That's an illusion caused by the break angle over the nut. If you center your eye/lens over the string instead of over the headstock that angle goes away.

 

Fender has been making basses that way since, oh, somewhere around 1951.

 

Tarnished pickguard screws?

 

I hate when that happens.