There are 3 different types of magazines for the 1922, 1922M1, 1922MII and M2 rifles. IIRC, they are not interchangeable, so you should check both rifle & magazine for compatibility. Brophy's 1903 Springfield book has the details.
About 5 years ago, I was shooting my M2 in league competition and had the magazines on my watch list. Genuine replacement magazines were hard to find and went for about $120. Someone was making replacement magazines out of some sort of polymer. At the time, the polymer magazines sold for $35 to $45. IIRC, SARCO was selling the replacement magazines.
I have seen polymer magazines for the Kimber 22 conversions of the 1911 Colt with the same packaging as the polymer M2 magazines. They appeared to be made by the same manufacturer. Maybe you can get a lead by looking for the pistol magazines.