Mags are around. Both military surplus and some no-name aftermarket ones. Military seem to run $20-25, after market $20. I have been told that the aftermarket ones are fine but never tried any. I would expect them to work since it's single stacked.
Lot of surplus ammo out there for them so ammo prices should be pretty good. Dans Ammo just had a bunch come in, check his site. It'll be corrosive but for the price I don't mind.