I was actually wondering about this too.
Prices aside, it is quite weird how hard it may be to find a magazine for a firearm unless it is extremely popular.
I realize designing an issue free magazine is no trivial task but once they have done it right what stops them from mass producing it?
Looking for mags for a 597. Here every online shop, if they do have the mag, has the darned fun-killer 'out of stock' sign -.-
(glad my gun came with 2 mags)