I did not see the magazines for your shotgun on Buds. The good this is, your firearm accepts Saiga 12 mags and they are relativity easy to find online.

Richard, yes but they are out od stock at Buds. The SDS LH-12 is based off the Saiga 12 and Can use easy to source Saiga 12 magazines, forearms,muzzle devices, grips and stocks. You can find the 12rd Magazine here : carolinashooterssupply.com/SAIGA_12_SUREFIRE_12RD_MAGAZINE_SGM_TACTICAL_AGP_p/sgm-s12-12rd-mag.htm

Buds does not seem to have these mags in stock. They're readily available from various outlets on the internet. Information also reveals Saiga 12 gauge shotgun mags are compatible.