It -looks- good to me... if I didn't know any better, I'd say someone already redid the wiring at some point. The type of shielding that's on the wires looks different than I usually see on the older machines. Do you know the history of the machine at all? Is there writing on the wires?
You see how the two wires have molded covering that looks like two wires glued together? Usually, the old machines have a "tube" of sorts to put the wires through, sort of like shrink tubing, but rubbery.
You mention that nothing feels crackly, and there's nothing missing, Does the wire shielding have any "gooey" spots? That's the other reason that the wiring needs to be replaced. It comes from oil getting on it and digesting it.
If you look here:
http://www.quiltingboard.com/vintage...r-t205360.html
and then follow to the link that Joe gives there to Rain's site, you'll see some examples of bad wiring. Joe's is (was) the worst I've seen yet.
That said, please don't just take my word for it. If you're concerned, take it to someone who would have a good idea. This could even be someone you know who's handy with electrical stuff, a handyman even. They should know what the wires should feel like.