Can you start with ships that have non-common craftsmanship components?

and

Is there a range for the Stripping the Husk navigator power?

No particular reason you couldn't, but obviously subject to availability and affordability.

No rules about it, but I'd assume 15m like the other Navigator powers.

To start with a good quality component, take a normal component, and increase SP cost by 1., and make modifications for good quality.

To start with a best quality component, take a normal component and increase SP cost by 2, and make modification for best quality.

Character creation is the only time you increase SP cost.

After character creation is the usual -10/-30 to aquisition rolls.