This sounds like a great idea. It would be nice though if Sanders or some other domestic producer would build a 10 round magazine for the 20 Gauge Saiga shotgun, in either 2.75" and/or 3". This way, people in states like Ohio where you can't buy a shotgun magazine with a capacity larger than 10 rounds can buy it. I can't buy the Sander's 13 round magazine because of my state's laws, and the available four round magazines just don't cut it.
The do-it-yourself project sounds neat, but is it very economical, especially with the four round mags for the Saiga 20 gauge running about $40 apiece?