As Winds stated do not take offense! When I read it I knew the gang was going to have a little fun with you! So Smile and have a great time. Cheaper than dirt does have some good products at a fair price. But most magazines are not interchangeable unless you are dealing with some sort fo AR or 1911 or similar platforms. And some manufacturers can advise if some magazines are interchangeable. Numrich Arms sometimes has hard to find magazines for pistols.
For example my Korean K-1 Daewoo will use regular M-16 and AR-15 Mags! And obviously a 1911 Colt Mag will work in a Springfield or Kimber of the same size.