You will need to call S&W to find out.
Yes. 9mm Luger is the 9x19 cartridge, also known as the 9mm Parabellum, and that's what the 9mm Sigma is chambered for.
9mm Luger. Ball or hollow point.
Either the SIG or S&W
You can download or request a manual via mail from the S&W web site
Recommend you find a good gunsmith or contact S&W and ask for an owner's manual.
Best left to a gunsmith. S&W will send you a owner's manual for free.
300 or so
9mm semi-automatic handgun.
100-400 USD or so
Needs to be examined by a gunsmith to be safe and sure. Although S&W and the Luger both fire the 9mm cartridge.
No. The mags for the 9mm are different than the mags for a .40 S&W