Desert Eagle .50AE black oxide

Israeli made 50AE compatible with newer US platform 6" bbl, black oxide finish.  Fired @ 200 times, better than 95% condition, but original magazine went for ride in back of wifes pickup for a month and now has most of the finish worn off, but works fine.  Purchased 2 new aftermarket mags, but don't know how they work Comes with original box, 3 mags and papers. Gun in custody of my FFL guy.  Send him certified check or USPS Money Order only.  Thanx