I'm coming upon possession of a XDsc9. My local guy has advised me that it is better to buy certain mags online than through him (don't you just love an honest shop?).

Are all XD mags the same in 9mm? Or does the sc take a smaller one?

Where would be the best place to buy mags from online, specifically high-cap xd sc 9s? Other than ammo and guns, never bought any gunstuffs online.

Thanks.